LiDAR device

ABSTRACT

A lidar device comprises: a laser emitting unit for including a plurality of VCSEL elements emitting a laser beam; a metasurface for including a plurality of beam steering cells arranged in a form of two-dimensional array by a row direction and a column direction, wherein the plurality of beam steering cells guide the laser beam by using nanopillars; wherein the nanopillars included in the plurality of beam steering cells form a subwavelength pattern, wherein the increase of an attribute related to at least one of the width, height, and number per unit length of the nanopillars is repetitive along the direction from the center of the metasurface to the position of the row corresponding to the plurality of beam steering cells.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 16/283,542, filed on Feb. 22, 2019, which claimspriority to and the benefit of U.S. Patent Application No. 62/671,305,filed on May 14, 2018, U.S. Patent Application No. 62/723,804, filed onAug. 28, 2018, Korean Patent Application No. 10-2018-0081897, filed onJul. 13, 2018, Korean Patent Application No. 10-2018-0081898, filed onJul. 13, 2018, Korean Patent Application No. 10-2018-0100701, filed onAug. 27, 2018, Korean Patent Application No. 10-2018-0143972, filed onNov. 20, 2018, Korean Patent Application No. 10-2018-0143973, filed onNov. 20, 2018, and Korean Patent Application No. 10-2018-0143974, filedon Nov. 20, 2018, the disclosures of which are incorporated herein byreference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a light detection and ranging (LiDAR)device, and more particularly, to a LiDAR device for obtaininginformation on a distance to an obstacle by steering a laser beam usinga metasurface including a nanopillar.

BACKGROUND

In active use of edge-emitting lasers, in recent years, interest in thevertical cavity surface emitting laser (VCSEL) has been increasing. TheVCSEL is a semiconductor laser that emits a laser in a verticaldirection on an upper surface and has advantages in that it is easy tomass produce because of its simple manufacturing process and it is ableto be manufactured in a small size because of its high degree ofintegration.

The VCSEL has mostly been applied to the telecommunications field, butrecently, attempts to apply the VCSEL to the optical system have beenvigorously made. Particularly, with autonomous-driving vehicles being inthe spotlight, attempts to apply the VCSEL to a light detection andranging (LiDAR) device have been vigorously made.

SUMMARY OF THE INVENTION

In an embodiment, the present disclosure is directed to reducing thesize of a light detection and ranging (LiDAR) device by using a verticalcavity surface emitting laser (VCSEL) element.

In another embodiment, the present disclosure is directed to generatinga scanning point cloud by forming various subwavelength patterns usingnanopillars.

In still another embodiment, the present disclosure is directed torealizing a solid-state lidar device capable of three-dimensionalscanning using a metasurface.

Objectives of the present disclosure are not limited to those describedabove, and other unmentioned objectives should be clearly understood bythose of ordinary skill in art to which the present disclosure pertainsfrom the present specification and accompanying drawings.

An aspect of the present disclosure is directed to a lidar device formeasuring a distance to an obstacle within a field of view having avertical direction and a horizontal direction and being formed by aplurality of scanning points. The device may include a laser emittingunit including a plurality of VCSEL (Vertical Cavity Surface EmittingLaser) elements arranged in a form of array and emitting a laser beam; ametasurface including a plurality of beam steering cells arranged in aform of two-dimensional array having a row direction corresponding tothe vertical direction and a column direction corresponding to thehorizontal direction, wherein the plurality of the beam steering cellsguide the laser beam to the plurality of the scanning points by usingnanopillars disposed on an emission surface side of the laser emittingunit; wherein the nanopillars form a subwavelength pattern in theplurality of the beam steering cells, wherein the subwavelength patternof a specific cell among the plurality of the beam steering cellsincludes: an increment of a first attribute being repeated along adirection from a center of the metasurface to a row of the specific celland a change rate of the first attribute being increased according to adistance from the row of the specific cell to the center of themetasurface, an increment of a second attribute being repeated along adirection from the center of the metasurface to a column of the specificcell and a change rate of the second attribute being related to adistance from the column of the specific cell to the center of themetasurface, and wherein the first attribute is related to at least oneof a width, a height, and a number per unit length of the nanopillars,and the second attribute is related to at least one of a width, aheight, and a number per unit length of the nanopillars.

Another aspect of the present disclosure is directed to a laser emittingdevice, whose a field of view being formed by a plurality of scanningpoints distributed in a vertical direction and a horizontal direction,the device comprising: a laser emitting unit including a plurality ofVCSEL (Vertical Cavity Surface Emitting Laser) elements arranged in aform of array and emitting a laser beam; a metasurface including aplurality of beam steering cells arranged in a form of two-dimensionalarray having a row direction corresponding to the vertical direction anda column direction corresponding to the horizontal direction, whereinthe plurality of the beam steering cells guide the laser beam to theplurality of the scanning points by using nanopillars disposed on anemission surface side of the laser emitting unit; wherein thenanopillars form a subwavelength pattern in the plurality of the beamsteering cells, wherein the subwavelength pattern of a specific cellamong the plurality of the beam steering cells includes: an increment ofa first attribute being repeated along a direction from a center of themetasurface to a row of the specific cell and a change rate of the firstattribute being increased according to a distance from the row of thespecific cell to the center of the metasurface, an increment of a secondattribute being repeated along a direction from the center of themetasurface to a column of the specific cell and a change rate of thesecond attribute being increased according to a distance from the columnof the specific cell to the center of the metasurface, and wherein thefirst attribute is related to at least one of a width, a height, and anumber per unit length of the nanopillars, and, the second attribute isrelated to at least one of a width, a height, and a number per unitlength of the nanopillars.

Yet another aspect of the present disclosure is directed to a lidardevice for measuring a distance to an obstacle within a field of viewhaving a vertical direction and a horizontal direction and being formedby a plurality of scanning points, the device comprising: a laseremitting unit including a plurality of VCSEL (Vertical Cavity SurfaceEmitting Laser) elements arranged in a form of array and emitting alaser beam; a metasurface including a plurality of beam steering cellsguiding the laser beam to the plurality of the scanning points by usingnanopillars disposed on an emission surface side of the laser emittingunit; wherein the nanopillars form a subwavelength pattern in theplurality of the beam steering cells, wherein the subwavelength patternof a specific cell among the plurality of the beam steering cellsincludes: an increment of a first attribute being repeated along a firstcomponent of a steering direction in which the specific cell guides thelaser beam and a change rate of the first attribute being increasedaccording to a magnitude of the first component, an increment of asecond attribute being repeated along a second component of a steeringdirection in which the specific cell guides the laser beam and a changerate of the second attribute being increased according to a magnitude ofthe second component, and wherein the first component corresponds to thevertical direction of the field of view and the second componentcorresponds to the horizontal direction of the field of view.

Still yet another aspect of the present disclosure is directed to alaser emitting device whose a field of view being formed by a pluralityof scanning points distributed in a vertical direction and a horizontaldirection, the device comprising: a laser emitting unit including aplurality of VCSEL (Vertical Cavity Surface Emitting Laser) elementsarranged in a form of array and emitting a laser beam; a metasurfaceincluding a plurality of beam steering cells guiding the laser beam tothe plurality of the scanning points by using nanopillars disposed on anemission surface side of the laser emitting unit; wherein thenanopillars form a subwavelength pattern in the plurality of the beamsteering cells, wherein the subwavelength pattern of a specific cellamong the plurality of the beam steering cells includes: an increment ofa first attribute being repeated along a first component of a steeringdirection in which the specific cell guides the laser beam and a changerate of the first attribute being increased according to a magnitude ofthe first component, an increment of a second attribute being repeatedalong a second component of a steering direction in which the specificcell guides the laser beam and a change rate of the second attributebeing increased according to a magnitude of the second component, andwherein the first component corresponds to the vertical direction of thefield of view and the second component corresponds to the horizontaldirection of the field of view.

Further still another aspect of the present disclosure is directed to alidar device for measuring a distance to an obstacle within a field ofview having a vertical direction and a horizontal direction and beingformed by a plurality of scanning points, the device comprising: a laseremitting unit including a plurality of VCSEL (Vertical Cavity SurfaceEmitting Laser) elements arranged in a form of array and emitting alaser beam; a metasurface including a plurality of beam steering cellsarranged in a form of two-dimensional array having a row directioncorresponding to the vertical direction and a column directioncorresponding to the horizontal direction, wherein the plurality of thebeam steering cells guide the laser beam to the plurality of thescanning points by using nanopillars disposed on an emission surfaceside of the laser emitting unit; wherein the plurality of the beamsteering cells include a first cell, a second cell being located at asame row and on a right side of the first cell, and a third cell beinglocated at a same column and on a lower side of the first cell, whereinthe nanopillars included in each of the first, the second and the thirdcells form a subwavelength pattern in each of the first, the second andthe third cells, wherein the subwavelength pattern in each of the first,the second and the third cells includes: an increment of a firstattribute being repeated along a direction from a center of themetasurface to a row of each of the first, the second and the thirdcells, respectively, and an increment of a second attribute beingrepeated along a direction from a center of the metasurface to a columnof each of the first, the second and the third cells, respectively, andwherein the first attribute is related to at least one of a width, aheight, and a number per unit length of the nanopillars and the secondattribute is related to at least one of a width, a height, and a numberper unit length of the nanopillars, in case that the first to the thirdcells are located on a upper left quadrant side among a quadrant of themetasurface, a change rate of the second attribute of the subwavelengthpattern in the first cell is greater than a change rate of the secondattribute of the subwavelength pattern in the second cell and a changerate of the first attribute of the subwavelength pattern in the firstcell is greater than a change rate of the first attribute of thesubwavelength pattern in the third cell.

Further still another aspect of the present disclosure is directed to alidar device for measuring a distance to an obstacle within a field ofview having a vertical direction and a horizontal direction and beingformed by a plurality of scanning points, the device comprising: a laseremitting unit including a plurality of VCSEL (Vertical Cavity SurfaceEmitting Laser) elements arranged in a form of array and emitting alaser beam; a first metasurface including a plurality of first beamsteering cells arranged in a form of one-dimensional array along a firstdirection, wherein the plurality of the first beam steering cells guidethe laser beam along a first steering direction corresponding to one ofthe vertical direction and the horizontal direction by using nanopillarsdisposed on an emission surface side of the laser emitting unit; asecond metasurface including a plurality of second beam steering cellsarranged in a form of one-dimensional array along a second directionperpendicular to the first direction, wherein the plurality of thesecond beam steering cells guide the laser beam along a second steeringdirection corresponding to another of the vertical direction or thehorizontal direction by using nanopillars disposed on an emissionsurface side of the laser emitting unit; wherein the nanopillarsincluded in the plurality of the first beam steering cells form a firstsubwavelength pattern, wherein the first subwavelength pattern includesan increment of a first attribute repeated along the first steeringdirection, the first attribute being related to at least one of a width,a height, and a number per unit length of the nanopillars, and wherein achange rate of the first attribute is greater in a first specific cellof the first beam steering cell than at a second specific cell of thefirst beam steering cell when an angle of the first steering directionof the first specific cell is greater than that of the second specificcell, wherein the nanopillars included in the plurality of the secondbeam steering cells form a second subwavelength pattern, wherein thesecond subwavelength pattern includes an increment of a second attributerepeated along the second steering direction, the second attribute beingrelated to at least one of a width, a height, and a number per unitlength of the nanopillars, and wherein a change rate of the secondattribute is greater in a third specific cell of the second beamsteering cell than at a fourth specific cell of the second beam steeringcell when an angle of the second steering direction of the thirdspecific cell is greater than that of the fourth specific cell.

Further still another aspect of the present disclosure is directed to alaser emitting device whose a field of view being formed by a pluralityof scanning points distributed in a vertical direction and a horizontaldirection, the device comprising: a laser emitting unit including aplurality of VCSEL (Vertical Cavity Surface Emitting Laser) elementsarranged in a form of array and emitting a laser beam; a firstmetasurface including a plurality of first beam steering cells arrangedin a form of one-dimensional array along a first direction, wherein theplurality of the first beam steering cells guide the laser beam along afirst steering direction corresponding to one of the vertical directionand the horizontal direction by using nanopillars disposed on anemission surface side of the laser emitting unit; a second metasurfaceincluding a plurality of second beam steering cells arranged in a formof one-dimensional array along a second direction perpendicular to thefirst direction, wherein the plurality of the second beam steering cellsguide the laser beam along a second steering direction corresponding toanother of the vertical direction or the horizontal direction by usingnanopillars disposed on an emission surface side of the laser emittingunit; wherein the nanopillars included in the plurality of the firstbeam steering cells form a first subwavelength pattern, wherein thefirst subwavelength pattern includes an increment of a first attributerepeated along the first steering direction, the first attribute beingrelated to at least one of a width, a height, and a number per unitlength of the nanopillars, and wherein a change rate of the firstattribute is greater in a first specific cell of the first beam steeringcell than at a second specific cell of the first beam steering cell whenan angle of the first steering direction of the first specific cell isgreater than that of the second specific cell, wherein the nanopillarsincluded in the plurality of the second beam steering cells form asecond subwavelength pattern, wherein the second subwavelength patternincludes an increment of a second attribute repeated along the secondsteering direction, the second attribute being related to at least oneof a width, a height, and a number per unit length of the nanopillars,and wherein a change rate of the second attribute is greater in a thirdspecific cell of the second beam steering cell than at a fourth specificcell of the second beam steering cell when an angle of the secondsteering direction of the third specific cell is greater than that ofthe fourth specific cell.

Further still another aspect of the present disclosure is directed to alidar device for measuring a distance to an obstacle within a field ofview having a vertical direction and a horizontal direction and beingformed by a plurality of scanning points, the device comprising: a laseremitting unit including a plurality of VCSEL (Vertical Cavity SurfaceEmitting Laser) elements arranged in a form of array and emitting alaser beam; a first metasurface including a plurality of first beamsteering cells arranged in a form of one-dimensional array along a firstdirection, wherein the plurality of the first beam steering cells guidethe laser beam along a first steering direction corresponding to one ofthe vertical direction and the horizontal direction by using nanopillarsdisposed on an emission surface side of the laser emitting unit; asecond metasurface including a plurality of second beam steering cellsarranged in a form of one-dimensional array along a second directionperpendicular to the first direction, wherein the plurality of thesecond beam steering cells guide the laser beam along a second steeringdirection corresponding to another of the vertical direction or thehorizontal direction by using nanopillars disposed on an emissionsurface side of the laser emitting unit; wherein the nanopillarsincluded in the plurality of the first beam steering cells form a firstsubwavelength pattern, wherein the first subwavelength pattern includesan increment of a first attribute repeated along the first steeringdirection, the first attribute being related to at least one of a width,a height, and a number per unit length of the nanopillars, and wherein achange rate of the first attribute is greater in a first specific cellof the first beam steering cell than at a second specific cell of thefirst beam steering cell when a distance from a center of the firstmetasurface to the first specific cell is greater than a distance fromthe center of the first metasurface to the second specific cell, whereinthe nanopillars included in the plurality of the second beam steeringcells form a second subwavelength pattern, wherein the secondsubwavelength pattern includes an increment of a second attributerepeated along the second steering direction, the second attribute beingrelated to at least one of a width, a height, and a number per unitlength of the nanopillars, and wherein a change rate of the secondattribute is greater in a third specific cell of the second beamsteering cell than at a fourth specific cell of the second beam steeringcell when a distance from a center of the second metasurface to thethird specific cell is greater than a distance from the center of thesecond metasurface to the fourth specific cell.

Further still another aspect of the present disclosure is directed to alidar device comprising: a polygonal mirror rotating along a rotationalaxis, reflecting a laser beam provided from a side toward an object andreceiving a laser beam reflected from the object; a laser emittingmodule including a plurality of VCSEL (Vertical Cavity Surface EmittingLaser) elements emitting a laser beam toward the polygonal mirror andarranged along the rotational axis; a metasurface forming, via aplurality of nanopillars disposed on an emission surface side of thelaser emitting module, a beam of line pattern line pattern beingextended along the rotational axis using the laser beam emitted from thelaser emitting module; and a sensor unit receiving, via the polygonalmirror, the laser beam reflected from the object.

Further still another aspect of the present disclosure is directed to alidar device comprising: a laser emitting module for including aplurality of VCSEL (Vertical Cavity Surface Emitting Laser) elementsemitting a laser beam; a metasurface forming a beam of line patternextended along a first axis which is one of a vertical axis and ahorizontal axis, wherein the metasurface includes a plurality ofsteering cells steering the laser beam along the first axis by using ananopillar disposed on an emission surface side of the laser emittingmodule; a scanning mirror transforming the beam of line pattern to abeam of plane pattern and receiving a laser beam reflected from anobject, by being rotated along the first axis; and a sensor unit forreceiving the laser beam reflected from the object via the scanningmirror.

Means for achieving above-described objectives are not limited to thosedescribed above, and other unmentioned means for achieving theobjectives should be clearly understood by those of ordinary skill inart to which the present disclosure pertains from the presentspecification and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Above and other objects, features and advantages of the presentdisclosure will become more apparent to those of ordinary skill in artby describing exemplary embodiments thereof in detail with reference toaccompanying drawings, in which:

FIG. 1 is a pictorial diagram illustrating a laser emitting deviceaccording to an embodiment;

FIGS. 2 to 7 are cross-sectional views of a laser emitting deviceaccording to various embodiments;

FIGS. 8 to 14 are views for describing a beam steering unit according tovarious embodiments;

FIG. 15 is a pictorial diagram illustrating a laser beam emitted from alaser emitting device according to an embodiment;

FIG. 16 is a view illustrating a beam steering unit according to anembodiment;

FIG. 17 is a view illustrating a beam projection surface according to anembodiment;

FIG. 18 is a pictorial diagram illustrating a laser emitting deviceaccording to an embodiment;

FIG. 19 is a pictorial diagram illustrating a laser emitting deviceaccording to an embodiment;

FIG. 20 is an exploded perspective view of a laser emitting deviceaccording to an embodiment;

FIGS. 21 to 23 are exploded perspective views of a laser emitting deviceaccording to various embodiments viewed from the side;

FIGS. 24 to 26 are exploded perspective views of a laser emitting deviceaccording to various embodiments;

FIGS. 27 and 28 are exploded perspective views of the laser emittingdevice of FIG. 26 viewed from the side;

FIGS. 29 to 31 are block diagrams for describing a light detection andranging (LiDAR) device according to various embodiments;

FIGS. 32 to 35 are pictorial diagrams illustrating a lidar deviceaccording to various implementations;

FIG. 36 is a top view of the lidar device of FIG. 35 viewed from thetop; and

FIG. 37 is a view for describing a lidar device according to stillanother implementation.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The foregoing objects, features and advantages of the present disclosurewill become more apparent from the following detailed descriptionrelated to accompanying drawings. However, various modifications may beapplied to the present disclosure, and the present disclosure may havevarious embodiments. Hereinafter, specific embodiments, which areillustrated in the drawings, will be described in detail.

In the drawings, the thicknesses of layers and regions are exaggeratedfor clarity. When it is indicated that an element or layer is “on” or“above” another element or layer, this includes a case in which anotherlayer or element is interposed therebetween as well as a case in whichthe element or layer is directly above the other element or layer. Inprinciple, like reference numerals designate like elements throughoutthe specification. In the following description, like reference numeralsare used to designate elements which have the same function within thesame idea illustrated in the drawings of each embodiment.

When detailed description of known functions or configurations relatedto the present disclosure is deemed to unnecessarily blur the gist ofthe invention, the detailed description thereof will be omitted. Also,numerals (e.g., first, second, etc.) used in the description herein aremerely identifiers for distinguishing one element from another element.

In addition, the terms “module” and “unit” used to refer to elements inthe following description are given or used in combination only inconsideration of ease of writing the specification, and the termsthemselves do not have distinct meanings or roles.

According to one embodiment, a lidar device for measuring a distance toan obstacle within a field of view having a vertical direction and ahorizontal direction and being formed by a plurality of scanning pointsis provided. The device may include a laser emitting unit including aplurality of VCSEL (Vertical Cavity Surface Emitting Laser) elementsarranged in a form of array and emitting a laser beam; a metasurfaceincluding a plurality of beam steering cells arranged in a form oftwo-dimensional array having a row direction corresponding to thevertical direction and a column direction corresponding to thehorizontal direction, wherein the plurality of the beam steering cellsguide the laser beam to the plurality of the scanning points by usingnanopillars disposed on an emission surface side of the laser emittingunit; wherein the nanopillars form a subwavelength pattern in theplurality of the beam steering cells, wherein the subwavelength patternof a specific cell among the plurality of the beam steering cellsincludes: an increment of a first attribute being repeated along adirection from a center of the metasurface to a row of the specific celland a change rate of the first attribute being increased according to adistance from the row of the specific cell to the center of themetasurface, an increment of a second attribute being repeated along adirection from the center of the metasurface to a column of the specificcell and a change rate of the second attribute being related to adistance from the column of the specific cell to the center of themetasurface, and wherein the first attribute is related to at least oneof a width, a height, and a number per unit length of the nanopillars,and the second attribute is related to at least one of a width, aheight, and a number per unit length of the nanopillars.

Herein, a steering direction of the beam steering cell may have avertical component in a range of −M° to M° and a horizontal component ina range of −N° to N°, wherein N is greater than M.

Herein, a size of a component corresponding to the vertical direction ofthe steering direction of the plurality of beam steering cells maycorrespond to a location in the row direction of the beam steering cell;and a size of a component corresponding to the horizontal direction ofthe steering direction of the plurality of beam steering cells maycorrespond to a location in the column direction of the beam steeringcell.

Herein, a location of each of the plurality of scanning points includedin the field of view may be related to a location of the beam steeringcell.

Herein, a vertical location of each of the plurality of scanning pointsmay correspond to a row-direction location of the beam steering cell;and a horizontal location of each of the plurality of scanning pointsmay correspond to a column-direction location of the beam steering cell.

Herein, the nanopillars may have a cylindrical or polygonal columnshape.

According to another embodiment, a laser emitting device, whose a fieldof view being formed by a plurality of scanning points distributed in avertical direction and a horizontal direction, the device comprising: alaser emitting unit including a plurality of VCSEL (Vertical CavitySurface Emitting Laser) elements arranged in a form of array andemitting a laser beam; a metasurface including a plurality of beamsteering cells arranged in a form of two-dimensional array having a rowdirection corresponding to the vertical direction and a column directioncorresponding to the horizontal direction, wherein the plurality of thebeam steering cells guide the laser beam to the plurality of thescanning points by using nanopillars disposed on an emission surfaceside of the laser emitting unit; wherein the nanopillars form asubwavelength pattern in the plurality of the beam steering cells,wherein the subwavelength pattern of a specific cell among the pluralityof the beam steering cells includes: an increment of a first attributebeing repeated along a direction from a center of the metasurface to arow of the specific cell and a change rate of the first attribute beingincreased according to a distance from the row of the specific cell tothe center of the metasurface, an increment of a second attribute beingrepeated along a direction from the center of the metasurface to acolumn of the specific cell and a change rate of the second attributebeing increased according to a distance from the column of the specificcell to the center of the metasurface, and wherein the first attributeis related to at least one of a width, a height, and a number per unitlength of the nanopillars, and, the second attribute is related to atleast one of a width, a height, and a number per unit length of thenanopillars may be provided.

Herein, a size of a component corresponding to the vertical direction ofthe steering direction of the plurality of beam steering cells maycorrespond to a location in the row direction of the beam steering cell;and a size of a component corresponding to the horizontal direction ofthe steering direction of the plurality of beam steering cells maycorrespond to a location in the column direction of the beam steeringcell.

According to another embodiment, a lidar device for measuring a distanceto an obstacle within a field of view having a vertical direction and ahorizontal direction and being formed by a plurality of scanning points,the device comprising: a laser emitting unit including a plurality ofVCSEL (Vertical Cavity Surface Emitting Laser) elements arranged in aform of array and emitting a laser beam; a metasurface including aplurality of beam steering cells guiding the laser beam to the pluralityof the scanning points by using nanopillars disposed on an emissionsurface side of the laser emitting unit; wherein the nanopillars form asubwavelength pattern in the plurality of the beam steering cells,wherein the subwavelength pattern of a specific cell among the pluralityof the beam steering cells includes: an increment of a first attributebeing repeated along a first component of a steering direction in whichthe specific cell guides the laser beam and a change rate of the firstattribute being increased according to a magnitude of the firstcomponent, an increment of a second attribute being repeated along asecond component of a steering direction in which the specific cellguides the laser beam and a change rate of the second attribute beingincreased according to a magnitude of the second component, and whereinthe first component corresponds to the vertical direction of the fieldof view and the second component corresponds to the horizontal directionof the field of view may be provided.

Herein, a steering direction of the beam steering cell may have avertical component in a range of −M° to M° and a horizontal component ina range of −N° to N°, wherein N is greater than M.

Herein, the plurality of beam steering cells may be arranged in atwo-dimensional array in a row direction corresponding to the verticaldirection and a column direction corresponding to the horizontaldirection; wherein: a size of a component corresponding to the verticaldirection of the steering direction of the plurality of beam steeringcells may correspond to a location in the row direction of the beamsteering cell; and a size of a component corresponding to the horizontaldirection of the steering direction of the plurality of beam steeringcells may correspond to a location in the column direction of the beamsteering cell.

According to another embodiment, a laser emitting device whose a fieldof view being formed by a plurality of scanning points distributed in avertical direction and a horizontal direction, the device comprising: alaser emitting unit including a plurality of VCSEL (Vertical CavitySurface Emitting Laser) elements arranged in a form of array andemitting a laser beam; a metasurface including a plurality of beamsteering cells guiding the laser beam to the plurality of the scanningpoints by using nanopillars disposed on an emission surface side of thelaser emitting unit; wherein the nanopillars form a subwavelengthpattern in the plurality of the beam steering cells, wherein thesubwavelength pattern of a specific cell among the plurality of the beamsteering cells includes: an increment of a first attribute beingrepeated along a first component of a steering direction in which thespecific cell guides the laser beam and a change rate of the firstattribute being increased according to a magnitude of the firstcomponent, an increment of a second attribute being repeated along asecond component of a steering direction in which the specific cellguides the laser beam and a change rate of the second attribute beingincreased according to a magnitude of the second component, and whereinthe first component corresponds to the vertical direction of the fieldof view and the second component corresponds to the horizontal directionof the field of view may be provided.

According to another embodiment, a lidar device for measuring a distanceto an obstacle within a field of view having a vertical direction and ahorizontal direction and being formed by a plurality of scanning points,the device comprising: a laser emitting unit including a plurality ofVCSEL (Vertical Cavity Surface Emitting Laser) elements arranged in aform of array and emitting a laser beam; a metasurface including aplurality of beam steering cells arranged in a form of two-dimensionalarray having a row direction corresponding to the vertical direction anda column direction corresponding to the horizontal direction, whereinthe plurality of the beam steering cells guide the laser beam to theplurality of the scanning points by using nanopillars disposed on anemission surface side of the laser emitting unit; wherein the pluralityof the beam steering cells include a first cell, a second cell beinglocated at a same row and on a right side of the first cell, and a thirdcell being located at a same column and on a lower side of the firstcell, wherein the nanopillars included in each of the first, the secondand the third cells form a subwavelength pattern in each of the first,the second and the third cells, wherein the subwavelength pattern ineach of the first, the second and the third cells includes: an incrementof a first attribute being repeated along a direction from a center ofthe metasurface to a row of each of the first, the second and the thirdcells, respectively, and an increment of a second attribute beingrepeated along a direction from a center of the metasurface to a columnof each of the first, the second and the third cells, respectively, andwherein the first attribute is related to at least one of a width, aheight, and a number per unit length of the nanopillars and the secondattribute is related to at least one of a width, a height, and a numberper unit length of the nanopillars, in case that the first to the thirdcells are located on a upper left quadrant side among a quadrant of themetasurface, a change rate of the second attribute of the subwavelengthpattern in the first cell is greater than a change rate of the secondattribute of the subwavelength pattern in the second cell and a changerate of the first attribute of the subwavelength pattern in the firstcell is greater than a change rate of the first attribute of thesubwavelength pattern in the third cell may be provided.

According to another embodiment, a lidar device for measuring a distanceto an obstacle within a field of view having a vertical direction and ahorizontal direction and being formed by a plurality of scanning points,the device comprising: a laser emitting unit including a plurality ofVCSEL (Vertical Cavity Surface Emitting Laser) elements arranged in aform of array and emitting a laser beam; a first metasurface including aplurality of first beam steering cells arranged in a form ofone-dimensional array along a first direction, wherein the plurality ofthe first beam steering cells guide the laser beam along a firststeering direction corresponding to one of the vertical direction andthe horizontal direction by using nanopillars disposed on an emissionsurface side of the laser emitting unit; a second metasurface includinga plurality of second beam steering cells arranged in a form ofone-dimensional array along a second direction perpendicular to thefirst direction, wherein the plurality of the second beam steering cellsguide the laser beam along a second steering direction corresponding toanother of the vertical direction or the horizontal direction by usingnanopillars disposed on an emission surface side of the laser emittingunit; wherein the nanopillars included in the plurality of the firstbeam steering cells form a first subwavelength pattern, wherein thefirst subwavelength pattern includes an increment of a first attributerepeated along the first steering direction, the first attribute beingrelated to at least one of a width, a height, and a number per unitlength of the nanopillars, and wherein a change rate of the firstattribute is greater in a first specific cell of the first beam steeringcell than at a second specific cell of the first beam steering cell whenan angle of the first steering direction of the first specific cell isgreater than that of the second specific cell, wherein the nanopillarsincluded in the plurality of the second beam steering cells form asecond subwavelength pattern, wherein the second subwavelength patternincludes an increment of a second attribute repeated along the secondsteering direction, the second attribute being related to at least oneof a width, a height, and a number per unit length of the nanopillars,and wherein a change rate of the second attribute is greater in a thirdspecific cell of the second beam steering cell than at a fourth specificcell of the second beam steering cell when an angle of the secondsteering direction of the third specific cell is greater than that ofthe fourth specific cell may be provided.

Herein, the first metasurface may include a first support layerconfigured to support the nanopillars included in the first beamsteering cell; and the second metasurface may include a second supportlayer configured to support the nanopillars included in the second beamsteering cell.

Herein, a refractive index of the first support layer may be equal to arefractive index of the second support layer.

Herein, a refractive index of the first support layer may be lower thana refractive index of the nanopillars included in the first beamsteering cell.

Herein, the plurality of first beam steering cells may guide the laserbeam in the vertical direction; and the plurality of second beamsteering cells may guide the laser beam in the horizontal direction.

Herein, a length in the first steering direction of the firstmetasurface may be smaller than a length in the first steering directionof the second metasurface.

Herein, a change rate of the first attribute may be lower than a changerate of the second attribute.

Herein, an angle range of an axis which is perpendicular to the firstmetasurface of the laser beam after passing through the firstmetasurface may be from −45° to 45°, and an angle range of the axis ofthe laser beam after passing through the second metasurface may be from−90° to 90°.

Herein, a location of each of the plurality of scanning points includedin the field of view may be related to at least one of a location of thefirst beam steering cell and a location of the second beam steeringcell.

According to another embodiment, a laser emitting device whose a fieldof view being formed by a plurality of scanning points distributed in avertical direction and a horizontal direction, the device comprising: alaser emitting unit including a plurality of VCSEL (Vertical CavitySurface Emitting Laser) elements arranged in a form of array andemitting a laser beam; a first metasurface including a plurality offirst beam steering cells arranged in a form of one-dimensional arrayalong a first direction, wherein the plurality of the first beamsteering cells guide the laser beam along a first steering directioncorresponding to one of the vertical direction and the horizontaldirection by using nanopillars disposed on an emission surface side ofthe laser emitting unit; a second metasurface including a plurality ofsecond beam steering cells arranged in a form of one-dimensional arrayalong a second direction perpendicular to the first direction, whereinthe plurality of the second beam steering cells guide the laser beamalong a second steering direction corresponding to another of thevertical direction or the horizontal direction by using nanopillarsdisposed on an emission surface side of the laser emitting unit; whereinthe nanopillars included in the plurality of the first beam steeringcells form a first subwavelength pattern, wherein the firstsubwavelength pattern includes an increment of a first attributerepeated along the first steering direction, the first attribute beingrelated to at least one of a width, a height, and a number per unitlength of the nanopillars, and wherein a change rate of the firstattribute is greater in a first specific cell of the first beam steeringcell than at a second specific cell of the first beam steering cell whenan angle of the first steering direction of the first specific cell isgreater than that of the second specific cell, wherein the nanopillarsincluded in the plurality of the second beam steering cells form asecond subwavelength pattern, wherein the second subwavelength patternincludes an increment of a second attribute repeated along the secondsteering direction, the second attribute being related to at least oneof a width, a height, and a number per unit length of the nanopillars,and wherein a change rate of the second attribute is greater in a thirdspecific cell of the second beam steering cell than at a fourth specificcell of the second beam steering cell when an angle of the secondsteering direction of the third specific cell is greater than that ofthe fourth specific cell may be provided.

According to another embodiment, a lidar device for measuring a distanceto an obstacle within a field of view having a vertical direction and ahorizontal direction and being formed by a plurality of scanning points,the device comprising: a laser emitting unit including a plurality ofVCSEL (Vertical Cavity Surface Emitting Laser) elements arranged in aform of array and emitting a laser beam; a first metasurface including aplurality of first beam steering cells arranged in a form ofone-dimensional array along a first direction, wherein the plurality ofthe first beam steering cells guide the laser beam along a firststeering direction corresponding to one of the vertical direction andthe horizontal direction by using nanopillars disposed on an emissionsurface side of the laser emitting unit; a second metasurface includinga plurality of second beam steering cells arranged in a form ofone-dimensional array along a second direction perpendicular to thefirst direction, wherein the plurality of the second beam steering cellsguide the laser beam along a second steering direction corresponding toanother of the vertical direction or the horizontal direction by usingnanopillars disposed on an emission surface side of the laser emittingunit; wherein the nanopillars included in the plurality of the firstbeam steering cells form a first subwavelength pattern, wherein thefirst subwavelength pattern includes an increment of a first attributerepeated along the first steering direction, the first attribute beingrelated to at least one of a width, a height, and a number per unitlength of the nanopillars, and wherein a change rate of the firstattribute is greater in a first specific cell of the first beam steeringcell than at a second specific cell of the first beam steering cell whena distance from a center of the first metasurface to the first specificcell is greater than a distance from the center of the first metasurfaceto the second specific cell, wherein the nanopillars included in theplurality of the second beam steering cells form a second subwavelengthpattern, wherein the second subwavelength pattern includes an incrementof a second attribute repeated along the second steering direction, thesecond attribute being related to at least one of a width, a height, anda number per unit length of the nanopillars, and wherein a change rateof the second attribute is greater in a third specific cell of thesecond beam steering cell than at a fourth specific cell of the secondbeam steering cell when a distance from a center of the secondmetasurface to the third specific cell is greater than a distance fromthe center of the second metasurface to the fourth specific cell may beprovided.

Herein, a vertical location of each of the plurality of scanning pointsmay be related to a location of the first beam steering cell; and ahorizontal location of each of the plurality of scanning points may berelated to a location of the second beam steering cell.

According to another embodiment, a lidar device comprising: a polygonalmirror rotating along a rotational axis, reflecting a laser beamprovided from a side toward an object and receiving a laser beamreflected from the object; a laser emitting module including a pluralityof VCSEL (Vertical Cavity Surface Emitting Laser) elements emitting alaser beam toward the polygonal mirror and arranged along the rotationalaxis; a metasurface forming, via a plurality of nanopillars disposed onan emission surface side of the laser emitting module, a beam of linepattern line pattern being extended along the rotational axis using thelaser beam emitted from the laser emitting module; and a sensor unitreceiving, via the polygonal mirror, the laser beam reflected from theobject may be provided.

Herein, the metasurface may include a plurality of beam steering cellsarranged in the form of an array along the rotation axis and configuredto steer the emitted laser beam along the rotation axis.

Herein, a steering direction of the beam steering cell may be determinedby a location of the beam steering cell in the array.

Herein, the beam steering cell may include a first beam steering celllocated at the top of the array and a second beam steering cell locatedat the bottom of the array; and a direction of a rotation-axis componentof a first steering direction of the first beam steering cell may beopposite to a direction of a rotation-axis component of a secondsteering direction of the second beam steering cell.

Herein, a first point at which a first laser beam steered by the firstbeam steering cell is irradiated on the polygonal mirror may be locatedabove a second point at which a second laser beam steered by the secondbeam steering cell is irradiated on the polygonal mirror.

Herein, a length along the rotation axis of the beam of a line patternmay be smaller than a length along the rotation axis of the metasurface.

Herein, each of the plurality of beam steering cells may include theplurality of nanopillars; at least some of the plurality of nanopillarsmay form a subwavelength pattern in which at least one attribute among awidth, a height, and the number per unit length thereof increases in adirection from a center of the metasurface to a beam steering cell towhich some of the plurality of nanopillars belong; and a change rate ofthe attribute may become higher as a location of the beam steering cellis farther from the center of the metasurface.

Herein, the plurality of nanopillars may form a subwavelength pattern inwhich, along the rotation axis of the polygonal mirror, a change in atleast one attribute of a width, a height, and the number per unit lengththereof is repeated, and a change rate of the attribute may changeaccording to a location along the rotation axis.

Herein, a length along the rotation axis of the metasurface may besmaller than a length along the rotation axis of the polygonal mirror.

Herein, a length along the rotation axis of the metasurface may begreater than a length along the rotation axis of the polygonal mirror.

Herein, the laser emitting module may emit a laser beam in a directionperpendicular to the rotation axis of the polygonal mirror.

According to another embodiment, a lidar device comprising: a laseremitting module for including a plurality of VCSEL (Vertical CavitySurface Emitting Laser) elements emitting a laser beam; a metasurfaceforming a beam of line pattern extended along a first axis which is oneof a vertical axis and a horizontal axis, wherein the metasurfaceincludes a plurality of steering cells steering the laser beam along thefirst axis by using a nanopillar disposed on an emission surface side ofthe laser emitting module; a scanning mirror transforming the beam ofline pattern to a beam of plane pattern and receiving a laser beamreflected from an object, by being rotated along the first axis; and asensor unit for receiving the laser beam reflected from the object viathe scanning mirror may be provided.

Herein, the plurality of steering cells may be arranged in the form ofan array along the first axis; and a length along the first axis of thearray may be greater than a length thereof along a second axis, which isperpendicular to the first axis.

Herein, the scanning mirror may have a polygonal column shape includinga first reflective surface and a second reflective surface, which sharesone side with the first reflective surface, and rotates 360° about thefirst axis.

Herein, the scanning mirror may rotate about the first axis within apreset range; and a virtual line, along which the beam of a line patternformed by the metasurface extends, crosses the first axis.

FIG. 1 is a pictorial diagram illustrating a laser emitting device 1000according to an embodiment.

The laser emitting device 1000 according to an embodiment may emit alaser beam in various directions.

The laser emitting device 1000 according to an embodiment may include alaser emitting unit 100 and a beam steering unit 200.

The laser beam emitted from the laser emitting unit 100 may be steeredby the beam steering unit 200. Accordingly, laser beams of variousshapes may be formed. For example, the laser emitting device 1000 mayemit a laser beam in the form of a planar beam. As another example, thelaser emitting device 1000 may emit a laser beam in the form of a linearbeam. Alternatively, the laser emitting device 1000 may output a laserbeam in the form of a point light source.

Hereinafter, each configuration of the laser emitting device 1000 willbe described in detail.

The laser emitting unit 100 may emit a laser beam to one side. The beamsteering unit 200 may be disposed at one side of the laser emitting unit100 and steer the laser beam emitted from the laser emitting unit 100.The beam steering unit 200 may steer the emitted laser beam on the basisof a nanopattern formed by a plurality of nanopillars 10. Accordingly, aflight path of the laser beam emitted from the laser emitting unit 100may be determined by the nanopattern. The nanopattern may have the samemeaning as a subwavelength pattern.

The laser emitting unit 100 may emit laser beams having variouswavelengths. For example, the laser emitting unit 100 may emit a laserbeam whose wavelength is 905 nm. Alternatively, the laser emitting unit100 may emit a laser beam having a wavelength of 1550 nm.

The laser emitting unit 100 may be provided in the form of a flat panel.

The laser emitting unit 100 may include a support surface and anemission surface. The support surface and the emission surface may beparallel to each other.

The laser emitting unit 100 may emit a laser beam in a directionperpendicular to the support surface. Alternatively, the laser emittingunit 100 may emit a laser beam in a direction perpendicular to theemission surface.

The beam steering unit 200 may generate laser beams of various formsfrom the laser beam provided from one side. For example, the beamsteering unit 200 may generate a laser beam in the form of a linear beamfrom a laser beam in the form of a point light source. As anotherexample, the beam steering unit 200 may generate a laser beam in theform of a planar beam from a laser beam in the form of a point lightsource. As still another example, the beam steering unit 200 maygenerate a laser beam in the form of a planar beam from a laser beam inthe form of a linear beam.

The beam steering unit 200 may refract the laser beam emitted from thelaser emitting unit 100. For example, the beam steering unit 200 mayrefract the emitted laser beam on the basis of a nanopattern formed bythe plurality of nanopillars 10. An angle-after-refraction of therefracted laser beam may be set on the basis of the nanopattern.

The beam steering unit 200 may include the plurality of nanopillars 10.

The plurality of nanopillars 10 may have a subwavelength size. Forexample, a pitch between the plurality of nanopillars 10 may be lessthan a wavelength of the laser beam emitted from the laser emitting unit100. Alternatively, a width, diameter, and height of the nanopillars 10may be less than a size of the wavelength of the laser beam.

The beam steering unit 200 may be a metasurface.

The beam steering unit 200 may adjust a phase of a laser beam emittedfrom the laser emitting unit 100 to refract the laser beam.

The beam steering unit 200 may be disposed on the laser emitting unit100. For example, the beam steering unit 200 may be disposed at theemission surface side of the laser emitting unit 100.

Alternatively, the beam steering unit 200 may be deposited on the laseremitting unit 100. The plurality of nanopillars 10 may be formed on anupper portion of the laser emitting unit 100. The plurality ofnanopillars 10 may form various nanopatterns on the laser emitting unit100.

The nanopillars 10 may have various shapes. For example, the nanopillars10 may have a cylindrical shape, a polygonal column shape, a conicalshape, a polypyramid shape, or the like. Furthermore, the nanopillars 10may have an irregular shape.

FIG. 2 is a cross-sectional view of a laser emitting device 1000according to an embodiment.

As illustrated in FIG. 2, the laser emitting device 1000 according to anembodiment may include a laser emitting unit 100 and a beam steeringunit 200.

Each configuration of the laser emitting device 1000 will be describedin detail below.

The laser emitting unit 100 according to an embodiment may include asubstrate 110 electrically connected to an external power source, alight source unit 120 configured to emit a laser beam, and reflectionunits 130 and 140 configured to reflect the laser beam emitted from thelight source unit 120.

The laser beam emitted from the light source unit 120 may oscillate bybeing reflected by the reflection units 130 and 140. The emitted laserbeam may be repeatedly reflected by a first reflection unit 130 and asecond reflection unit 140 and then pass through the second reflectionunit 140 to be emitted to the outside of the laser emitting unit 100.

The light source unit 120 may emit laser beams of various wavelengths.For example, the light source unit 120 may emit a laser beam whosewavelength is 905 nm. Alternatively, the light source unit 120 may emita laser beam having a wavelength of 1550 nm.

The light source unit 120 may be formed of various materials. Forexample, the light source unit 120 may include GaAs, AlGaAs, GaAlAs, andSi.

A wavelength of a laser beam emitted from the light source unit 120 mayvary according to materials constituting the light source unit 120.

An intensity of a laser beam emitted from the light source unit 120 mayvary according to a strength of power received from the outside.

The light source unit 120 may be disposed between the first reflectionunit 130 and the second reflection unit 140.

The first reflection unit 130 may reflect a laser beam provided to oneside. For example, the first reflection unit 130 may reflect a laserbeam emitted from the light source unit 120 toward the light source unit120. The first reflection unit 130 may reflect a laser beam reflectedfrom the second reflection unit 140 toward the light source unit 120.

The first reflection unit 130 may include a plurality of layers. Theplurality of layers may have a structure in which a layer having arelatively high refractive index and a layer having a relatively lowrefractive index are alternately disposed. Each of the plurality oflayers may have a thickness that is ¼ of a wavelength of a laser beamemitted from the light source unit 120.

As illustrated, the first reflection unit 130 may be disposed on anupper portion of the substrate 110. For example, the first reflectionunit 130 may be deposited on the substrate 110. Of course, anotherconfiguration may be included between the substrate 110 and the firstreflection unit 130.

The first reflection unit 130 may be a distributed Bragg reflector(DBR).

The first reflection unit 130 may include GaAs, indium tin oxide (ITO),indium zinc oxide (IZO), Ga—In—Zn-oxide (GIZO), Al—Zn-oxide (AZO),Ga—Zn-oxide (GZO), and ZnO.

The second reflection unit 140 may reflect a laser beam provided to oneside. For example, the second reflection unit 140 may reflect a laserbeam emitted from the light source unit 120 toward the light source unit120. The second reflection unit 140 may reflect the laser beam reflectedfrom the first reflection unit 130 toward the light source unit 120.

The second reflection unit 140 may include a plurality of layers. Theplurality of layers may have a structure in which a layer having arelatively high refractive index and a layer having a relatively lowrefractive index are alternately disposed. Each of the plurality oflayers may have a thickness that is ¼ of a wavelength of a laser beamemitted from the light source unit 120.

A laser beam that is emitted from the light source unit 120 and thenreflected by the first reflection unit 130 and the second reflectionunit 140 may pass through the second reflection unit 140 and be emittedtoward the nanopillars 10. The laser beam may be emitted in a directionperpendicular to the substrate 110.

The second reflection unit 140 may be disposed on an upper portion ofthe light source unit 120. For example, the second reflection unit 140may be deposited on the light source unit 120. Of course, anotherconfiguration may be included between the substrate 110 and the secondreflection unit 140.

The second reflection unit 140 may be a distributed Bragg reflector(DBR).

The second reflection unit 140 may include GaAs, CuAl₂O, NiO, and CuO.

An electrical attribute of the first reflection unit 130 may differ froman electrical attribute of the second reflection unit 140. For example,the first reflection unit 130 may be an n-type semiconductor, and thesecond reflection unit 140 may be a p-type semiconductor.

The first reflection unit 130 may include more layers than the secondreflection unit 140.

A reflectivity of the first reflection unit 130 may be higher than areflectivity of the second reflection unit 140.

The laser emitting unit 100 according to an embodiment may be a verticalcavity surface emitting laser (VCSEL) element. A laser beam emitted fromthe laser emitting unit 100 may be emitted in the directionperpendicular to the substrate 110. The emitted laser beam may beemitted in the direction perpendicular to the support surface of thelaser emitting unit 100.

In FIG. 2, the first reflection unit 130 is illustrated as beingdisposed between the substrate 110 and the light source unit 120.However, this is merely an example, and the locations of the firstreflection unit 130 and the second reflection unit 140 may also bereversed. The laser emitting unit 100 may also include configurationsother than the illustrated configurations.

Meanwhile, in FIG. 2, the nanopillars 10 and the second reflection unit140 are illustrated as being in contact with each other. However, thisis merely for convenience of the description, and another configurationmay be disposed between the nanopillars 10 and the second reflectionunit 140. For example, a transparent electrode layer may be disposedbetween the nanopillars 10 and the second reflection unit 140.

The beam steering unit 200 may refract a laser beam emitted from thelaser emitting unit 100. For example, the beam steering unit 200 maycontrol a phase of the laser beam to steer the laser beam. Also, thebeam steering unit 200 may control a light quantity of the laser beam tosteer the laser beam.

The beam steering unit 200 may include the plurality of nanopillars 10.

A height of the nanopillars 10 may be at least half or more of a heightof a wavelength of a laser beam emitted from the laser emitting unit100.

The nanopillars 10 may be formed of various materials. For example, thenanopillars 10 may be formed of metals such as As, Au, Al, and Pt ormetal nitrides such as TiN and TaN.

A refractive index of the nanopillars 10 may be higher than therefractive index of the second reflection unit 140.

The plurality of nanopillars 10 may form various nanopatterns. The beamsteering unit 200 may steer a laser beam emitted from the laser emittingunit 100 on the basis of the nanopatterns.

The nanopillars 10 may form nanopatterns on the basis of variousattributes. The attributes may include a width W, a pitch P, a height H,and a number per unit length of the nanopillars 10.

Hereinafter, nanopatterns formed on the basis of various attributes andlaser beam steering according to the nanopatterns will be described.

The plurality of nanopillars 10 may form nanopatterns on the basis ofthe width W thereof. For example, the plurality of nanopillars 10 may bedisposed such that widths W1, W2, and W3 thereof gradually increase inone direction. In this case, a laser beam emitted from the laseremitting unit 100 may be steered in the direction in which the width Wof the nanopillars 10 increases.

For example, the beam steering unit 200 may include a first nanopillar11 having a first width W1, a second nanopillar 12 having a second widthW2, and a third nanopillar 13 having a third width W3. The third widthW3 may be greater than the first width W1 and the second width W2. Thesecond width W2 may be greater than the first width W1. That is, thewidth W of the nanopillars 10 may gradually increase from the firstnanopillar 11 toward the third nanopillar 13. In this case, a laser beamemitted from the laser emitting unit 100 may be steered in a thirddirection, which is a direction between a first direction, in which thelaser beam is emitted from the laser emitting unit 100, and a seconddirection, which is a direction from the first nanopillar 11 to thethird nanopillar 13. The third direction may be calculated on the basisof the sum of a first vector having the first direction and a secondvector having the second direction. The second direction may beperpendicular to the first direction.

Meanwhile, a steering angle θ of the laser beam may vary according to achange rate of the width W of the nanopillars 10. Here, the change rateof the width W of the nanopillars 10 may refer to a numerical valueindicating, on average, a degree of change in the width W of theplurality of nanopillars 10 which are adjacent to each other. Here, thesteering angle θ may refer to an angle between a laser beam steered bythe beam steering unit 200 and a virtual reference line R. The referenceline R may relate to an emission direction of a laser beam emitted fromthe laser emitting unit 100. For example, the reference line R may beparallel to the emission direction.

The change rate of the width W of the nanopillars 10 may be calculatedon the basis of a difference between the first width W1 and the secondwidth W2 and a difference between the second width W2 and the thirdwidth W3.

The difference between the first width W1 and the second width W2 may bedifferent from the difference between the second width W2 and the thirdwidth W3.

The steering angle θ of the laser beam may vary according to the width Wof the nanopillars 10.

Specifically, the steering angle θ may increase as the change rate ofthe width W of the nanopillars 10 increases.

For example, the nanopillars 10 may form, on the basis of the width Wthereof, a first pattern having a first change rate. Also, thenanopillars 10 may form, on the basis of the width W thereof, a secondpattern having a second change rate which is lower than the first changerate.

In this case, a first steering angle due to the first pattern may belarger than a second steering angle due to the second pattern.

Meanwhile, the steering angle θ may be in a range of −90° to 90°.

The plurality of nanopillars 10 may form nanopatterns on the basis of achange in the pitch P between the nanopillars P adjacent to each other.The beam steering unit 200 may steer a laser beam emitted from the laseremitting unit 100 on the basis of the nanopatterns formed on the basisof the change in the pitch P between the nanopillars 10.

FIG. 3 is a cross-sectional view for describing beam steering accordingto changes in pitches P1, P2, and P3 between nanopillars 10. A laseremitting device 1000 may include a laser emitting unit 100 and a beamsteering unit 200. The beam steering unit 200 may include a plurality ofnanopillars 10.

The laser emitting unit 100 of FIG. 3 may correspond to the laseremitting unit 100 described above with reference to FIGS. 1 and 2.Accordingly, detailed description thereof will be omitted, anddifferences from the laser emitting device 1000 of FIG. 2 will mainly bedescribed.

According to an embodiment, a pitch P between the nanopillars 10 maygradually decrease in one direction. Here, the pitch P may refer to adistance between centers of two nanopillars 10 adjacent to each other.For example, a first pitch P1 may be defined as a distance between acenter of a first nanopillar 11 and a center of a second nanopillar 12.Alternatively, the first pitch P1 may be defined as the shortestdistance between the first nanopillar 11 and the second nanopillar 12.

A laser beam emitted from the laser emitting unit 100 may be steered ina direction in which the pitch P between the nanopillars 10 decreases.

The beam steering unit 200 may include a first nanopillar 11, a secondnanopillar 12, a third nanopillar 13, and a fourth nanopillar 14. Inthis case, a first pitch P1 may be obtained on the basis of a distancebetween the first nanopillar 11 and the second nanopillar 12. Likewise,a second pitch P2 may be obtained on the basis of a distance between thesecond nanopillar 12 and the third nanopillar 13. Also, a third pitch P3may be obtained on the basis of a distance between the third nanopillar13 and the fourth nanopillar 14. In this case, the first pitch P1 may begreater than the second pitch P2 and the third pitch P3. The secondpitch P2 may be greater than the third pitch P3. That is, the pitch Pgradually decreases from the first nanopillar 11 toward the fourthnanopillar 14.

In this case, a laser beam emitted from the laser emitting unit 100 maybe steered in a direction between a first direction in which the laserbeam is emitted from the laser emitting unit 100 and a second directionfrom the first nanopillar 11 to the third nanopillar 13.

The steering angle θ of the laser beam may vary according to the pitch Pbetween the nanopillars 10.

Specifically, the steering angle θ of the laser beam may vary accordingto a change rate of the pitch P between the nanopillars 10. Here, thechange rate of the pitch P between the nanopillars 10 may refer to anumerical value indicating, on average, a degree of change in the pitchP between the nanopillars 10 adjacent to each other.

The steering angle θ of the laser beam may increase as the change rateof the pitch P between the nanopillars 10 increases.

For example, the nanopillars 10 may form, on the basis of the pitch Ptherebetween, a first pattern having a first change rate. Also, thenanopillars 10 may form, on the basis of the pitch P therebetween, asecond pattern having a second change rate which is lower than the firstchange rate.

In this case, a first steering angle due to the first pattern may belarger than a second steering angle due to the second pattern.

Meanwhile, the above-described laser beam steering principle accordingto a change in the pitch P between the nanopillars 10 may be similarlyapplied even when the number of nanopillars 10 per unit length changes.

For example, when the number of nanopillars 10 per unit length changes,a laser beam emitted from the laser emitting unit 100 may be steered ina direction between a first direction in which the laser beam is emittedfrom the laser emitting unit 100 and a second direction in which thenumber of nanopillars 10 per unit length increases.

Meanwhile, the plurality of nanopillars 10 may form nanopatterns on thebasis of a change in a height H of the nanopillars 10.

FIG. 4 is a cross-sectional view for describing beam steering accordingto a change in a height H of the nanopillars 10. Referring to FIG. 4, alaser emitting device 1000 may include a laser emitting unit 100 and abeam steering unit 200. The beam steering unit 200 may include aplurality of nanopillars 10.

The laser emitting unit 100 of FIG. 4 may correspond to the laseremitting unit 100 described above with reference to FIGS. 1 and 2.Accordingly, detailed description thereof will be omitted, anddifferences from the laser emitting device 1000 of FIG. 2 will be mainlydescribed.

According to an embodiment, heights H1, H2, and H3 of the plurality ofnanopillars 10 may gradually increase in one direction. A laser beamemitted from the laser emitting unit 100 may be steered in a directionin which the height H of the nanopillars 10 increases.

For example, the beam steering unit 200 may include a first nanopillar11 having a first height H1, a second nanopillar 12 having a secondheight H2, and a third nanopillar 13 having a third height H3. The thirdheight H3 may be higher than the first height H1 and the second heightH2. The second height H2 may be higher than the first height H1. Thatis, the height H of the nanopillars 10 may gradually increase from thefirst nanopillar 11 to the third nanopillar 13. In this case, a laserbeam emitted from the laser emitting unit 100 may be steered in adirection between a first direction in which the laser beam is emittedfrom the laser emitting unit 100 and a second direction from the firstnanopillar 11 to the third nanopillar 13.

The steering angle θ of the laser beam may vary according to the heightH of the nanopillars 10.

Specifically, the steering angle θ of the laser beam may vary accordingto a change rate of the height H of the nanopillars 10. Here, the changerate of the height H of the nanopillars 10 may refer to a numericalvalue indicating, on average, a degree of change in the height H of thenanopillars 10 adjacent to each other.

The change rate of the height H of the nanopillars 10 may be calculatedon the basis of a difference between the first height H1 and the secondheight H2 and a difference between the second height H2 and the thirdheight H3. The difference between the first height H1 and the secondheight H2 may be different from the difference between the second heightH2 and the third height H3.

The steering angle θ of the laser beam may increase as the change rateof the height H of the nanopillars 10 increases.

For example, the nanopillars 10 may form, on the basis of the height Hthereof, a first pattern having a first change rate. Also, thenanopillars 10 may form, on the basis of the height H thereof, a secondpattern having a second change rate which is lower than the first changerate.

In this case, a first steering angle due to the first pattern may belarger than a second steering angle due to the second pattern.

Meanwhile, although in FIGS. 2 to 4, the first to fourth nanopillars 11,12, 13, and 14 are illustrated as being formed as one set on the laseremitting unit 100, a plurality of sets of nanopillars 10 may also formnanopatterns on a single laser emitting unit 100. For example, a newnanopattern in which the nanopatterns formed in FIGS. 2 to 4 arerepeated may be formed on the laser emitting unit 100.

Also, the nanopatterns formed in FIGS. 2 to 4 may be formed incombination with each other on a single laser emitting unit 100.

Hereinafter, a laser emitting device having various nanopatterns andlaser beam steering according to the nanopatterns will be described.

FIG. 5 is a cross-sectional view for describing a laser emitting device1000 according to an embodiment. Referring to FIG. 5, the laser emittingdevice 1000 may include a plurality of laser emitting units 101, 102,and 103. Also, the laser emitting device 1000 may include a beamsteering unit 200 including a plurality of nanopillars 10.

Laser beams emitted from the plurality of laser emitting units 101, 102,and 103 may be steered by the plurality of nanopillars 10 disposed onthe plurality of laser emitting units 101, 102, and 103.

Each configuration of the laser emitting device 1000 will be describedin detail below.

The laser emitting device 1000 may include a first laser emitting unit101, a second laser emitting unit 102, and a third laser emitting unit103. Meanwhile, the first to third laser emitting units 101, 102, and103 may correspond to the laser emitting unit 100 described above withreference to FIGS. 1 and 2. Accordingly, detailed description thereofwill be omitted.

The laser emitting unit 100 may be provided in the form of an array. Forexample, the laser emitting unit 100 may be provided in the form of a1×3 array. In this case, the first to third laser emitting units 101,102, and 103 may be respectively disposed in a first column to a thirdcolumn of an array.

The first to third laser emitting units 101, 102, and 103 may emit alaser beam in the same direction. For example, the first to third laseremitting units 101, 102, and 103 may emit a laser beam in a directionperpendicular to an emission surface of the laser emitting device 1000.

The beam steering unit 200 may be provided in the form of an array. Thebeam steering unit 200 may include a plurality of beam steering cells210. The beam steering cells 210 may include a first beam steering cell211, a second beam steering cell 212, and a third beam steering cell213. The plurality of beam steering cells 210 may be arranged in theform of an array.

The first to third beam steering cells 211, 212, and 213 may controlphases of laser beams emitted from the plurality of laser emitting units101, 102, and 103, respectively, to change irradiation directions of thelaser beams.

Also, the first to third beam steering cells 211, 212, and 213 maycontrol transmittances of laser beams emitted from the plurality oflaser emitting units 101, 102, and 103, respectively, to changeirradiation directions of the laser beams.

Each of the first to third beam steering cells 211, 212, and 213 mayinclude the plurality of nanopillars 10 forming nanopatterns. A laserbeam emitted from the laser emitting unit 100 may be steered by thenanopillars 10.

The nanopillars 10 may steer a laser beam emitted from the laseremitting unit 100 to form laser beams of various shapes.

For example, the nanopillars 10 may form a laser beam having a shapediverging from a center of the laser emitting unit 100. As anotherexample, the nanopillars 10 may form a laser beam having a shapeconverging toward an irradiation path of laser beams emitted from thelaser emitting unit 100 disposed at the center of the array. As stillanother example, the nanopillars 10 may form a laser beam irradiated ina direction perpendicular to a support surface of the laser emittingdevice 1000.

Hereinafter, for convenience of description, the case in which a laserbeam steered by the nanopillars 10 has a form of diverging from thecenter of the laser emitting unit 100 will be mainly described.

Meanwhile, the plurality of nanopillars 10 may form nanopatterns on thebasis of locations of beam steering cells 210. For example, thenanopillars 10 may form nanopatterns that cause a steering angle θ dueto a beam steering cell 210 far from the center of the beam steeringunit 200 to be larger than a steering angle θ due to a beam steeringcell 210 close to the center of the beam steering unit 200.

Such nanopatterns may be formed on the basis of above-described width Wof the nanopillars 10, pitch P between the nanopillars 10, and height Hof the nanopillars 10.

Referring to FIG. 5, the nanopillars 10 may form nanopatterns on thebasis of a change in the width W thereof and locations of the beamsteering cells 210.

Specifically, the second beam steering cell 212 located at a centralportion of the beam steering unit 200 may include a plurality ofnanopillars 10 having the same width W.

Also, the first beam steering cell 211 located farther from the centerof the beam steering unit 200 than the second beam steering cell 212 mayinclude a plurality of nanopillars 10 whose width W gradually increasesaway from the center of the beam steering unit 200.

Likewise, the third beam steering cell 213 located farther from thecenter of the beam steering unit 200 than the second beam steering cell212 may include a plurality of nanopillars 10 whose width W graduallyincreases away from the center of the beam steering unit 200.

Accordingly, the beam steering unit 200 may form a laser beam having adiverging shape.

Meanwhile, a first steering angle of the first beam steering celllocated far from the center of the beam steering unit 200 may be largerthan a second steering angle of the second beam steering cell locatedclose to the center of the beam steering unit 200.

In this case, a change rate of a width W of the nanopillars 10 includedin the first beam steering cell may be higher than a change rate of awidth W of the nanopillars 10 included in the second beam steering cell.

Meanwhile, in FIG. 5, laser beams steered by the first beam steeringcell 211 and the third beam steering cell 213 are each illustrated asnot crossing an extension line extending in an emission direction of alaser beam steered by the second beam steering cell 212. However,embodiments are not limited thereto, and the laser beams steered by thefirst beam steering cell 211 and the third beam steering cell 213, mayalso each cross the extension line.

Accordingly, the laser beam steered by the first beam steering cell 211may be steered in a direction between a first direction in which thelaser beam is emitted from the laser emitting unit 100 and a seconddirection from the first beam steering cell 211 to the center of thebeam steering unit 200.

Likewise, the laser beam steered by the third beam steering cell 213 maybe steered in a direction between a third direction in which the laserbeam is emitted from the laser emitting unit 100 and a fourth directionfrom the third beam steering cell 213 to the center of the beam steeringunit 200.

Meanwhile, the plurality of nanopillars 10 forming nanopatterns may formpatterns which are symmetrical about the center of the beam steeringunit 200. For example, a first nanopattern formed by the nanopillars 10included in the first beam steering cell 211 and a third nanopatternformed by the nanopillars 10 included in the third beam steering cell213 may be symmetrical to each other.

Accordingly, the first steering angle due to the first beam steeringcell 211 may be equal in size to the third steering angle due to thethird beam steering cell 213.

Meanwhile, the shapes of the nanopillars 10 included in the plurality ofbeam steering cells 210 may be different from each other. For example,the nanopillars 10 included in the first beam steering cell 211 may havea cylindrical shape, and the nanopillars 10 included in the second beamsteering cell 212 may have a polygonal column shape.

Also, the shapes of the plurality of nanopillars 10 included in the samebeam steering cell 210 may be different from each other. For example,some of the plurality of nanopillars 10 included in the first beamsteering cell 211 may have a cylindrical shape, and the remainingnanopillars 10 may have a polygonal column shape.

Meanwhile, steering angles θ of the plurality of beam steering cells 210may be different from each other. For example, the first steering angleof the first beam steering cell 211 and a third steering angle of thethird beam steering cell 213 may be different from each other.

Meanwhile, the plurality of laser emitting units 100 may be controlledindependently. For example, attributes (wavelength, intensity, shootingcycle, and the like) of laser beams emitted from each of the laseremitting units 100 may be different. Also, the on/off state of each ofthe laser emitting units 100 may be controlled separately.

For example, the laser emitting unit 100 may include a plurality ofVCSEL elements arranged in the form of an array. In this case, theon/off states of the plurality of VCSEL elements may be controlledindependently. That is, the laser emitting unit 100 may include anaddressable VCSEL array.

The laser emitting device 1000 may adjust the on/off state and intensityof each of the plurality of laser emitting units 100 to adjust steeringangles of laser beams.

Alternatively, the plurality of laser emitting units 100 may be linked.For example, the on/off states of the first laser emitting unit 101 andthe second laser emitting unit 102 may be controlled together.

The laser emitting device 1000 may emit laser beams of variouswavelengths. For example, the first laser emitting unit 101 may emit afirst laser beam having a first wavelength, and the second laseremitting unit 102 may emit a second laser beam having a secondwavelength.

FIG. 6 is a cross-sectional view for describing a laser emitting device1000 according to another embodiment. Referring to FIG. 6, the laseremitting device 1000 may include a plurality of laser emitting units100. Also, the laser emitting device 1000 may include a beam steeringunit 200 including a plurality of nanopillars 10. The beam steering unit200 may include a plurality of beam steering cells 210.

Laser beams emitted from the plurality of laser emitting units 100 maybe steered by a plurality of nanopillars 10 included in the plurality ofbeam steering cells 210.

Each configuration of the laser emitting device 1000 will be describedin detail below.

The laser emitting device 1000 may include a first laser emitting unit101, a second laser emitting unit 102, and a third laser emitting unit103. The beam steering cells 210 may include a first beam steering cell211, a second beam steering cell 212, and a third beam steering cell213.

Meanwhile, the first to third laser emitting units 101, 102, and 103 maycorrespond to the laser emitting unit 100 described above with referenceto FIGS. 1, 2, and 5. Accordingly, detailed description thereof will beomitted, and differences from the laser emitting device 1000 of FIG. 5will be mainly described.

Referring to FIG. 6, the nanopillars 10 may form nanopatterns on thebasis of a change in a pitch P therebetween and locations of the beamsteering cells 210.

Specifically, the second beam steering cell 212 located at the centralportion of the beam steering unit 200 may include a plurality ofnanopillars 10 disposed at equal pitches P.

Also, the first beam steering cell 211 located farther from the centerof the beam steering unit 200 than the second beam steering cell 212 mayinclude a plurality of nanopillars 10 which are disposed at a pitch Pwhich gradually increases away from the center of the beam steering unit200.

Likewise, the third beam steering cell 213 located farther from thecenter of the beam steering unit 200 than the second beam steering cell212 may include a plurality of nanopillars 10 which are disposed at apitch P which gradually increases away from the center of the beamsteering unit 200.

Accordingly, the beam steering unit 200 may form a laser beam having adiverging shape.

Meanwhile, a first steering angle of the first beam steering celllocated far from the center of the beam steering unit 200 may be largerthan a second steering angle of the second beam steering cell locatedclose to the beam steering unit 200.

In this case, a change rate of a pitch P between the nanopillars 10included in the first beam steering cell may be higher than a changerate of a pitch P between the nanopillars 10 included in the second beamsteering cell.

Meanwhile, the above-described laser beam steering principle accordingto a change in the pitch P between the nanopillars 10 may be similarlyapplied even when the number of nanopillars 10 per unit length changes.

For example, the plurality of nanopillars 10 included in the first beamsteering cell 211 may form a nanopattern in which the number ofnanopillars 10 per unit length gradually increases away from the centerof the beam steering unit 200.

Likewise, the plurality of nanopillars 10 included in the third beamsteering cell 213 may form a nanopattern in which the number ofnanopillars 10 per unit length gradually increases away from the centerof the beam steering unit 200.

Also, the plurality of nanopillars 10 included in the second beamsteering cell 212 located at the central portion of the beam steeringunit 200 may form a nanopattern in which the number of nanopillars 10per unit length is constant.

FIG. 7 is a cross-sectional view for describing a laser emitting device1000 according to still another embodiment. Referring to FIG. 7, thelaser emitting device 1000 may include a plurality of laser emittingunits 100. Also, the laser emitting device 1000 may include a beamsteering unit 200 including a plurality of nanopillars 10. The beamsteering unit 200 may include a plurality of beam steering cells 210.

Laser beams emitted from the plurality of laser emitting units 100 maybe steered by a plurality of nanopillars 10 included in the plurality ofbeam steering cells 210.

Each configuration of the laser emitting device 1000 will be describedin detail below.

The laser emitting device 1000 may include a first laser emitting unit101, a second laser emitting unit 102, and a third laser emitting unit103. The beam steering cells 210 may include a first beam steering cell211, a second beam steering cell 212, and a third beam steering cell213.

Meanwhile, the first to third laser emitting units 101, 102, and 103 maycorrespond to the laser emitting unit 100 described above with referenceto FIGS. 1, 2, and 5. Accordingly, detailed description thereof will beomitted, and differences from the laser emitting device 1000 of FIG. 5will be mainly described.

Referring to FIG. 7, the nanopillars 10 may form nanopatterns on thebasis of a change in a height H thereof and locations of the beamsteering cells 210.

Specifically, the second beam steering cell 212 located at the centralportion of the beam steering unit 200 may include a plurality ofnanopillars 10 having the same height H.

Also, the first beam steering cell 211 located farther from the centerof the beam steering unit 200 than the second beam steering cell 212 mayinclude a plurality of nanopillars 10 whose height H gradually increasesaway from the center of the beam steering unit 200.

Likewise, the third beam steering cell 213 located farther from thecenter of the beam steering unit 200 than the second beam steering cell212 may include a plurality of nanopillars 10 whose height H graduallyincreases away from the center of the beam steering unit 200.

Accordingly, the beam steering unit 200 may form a laser beam having adiverging shape.

Meanwhile, a first steering angle of the first beam steering celllocated far from the center of the beam steering unit 200 may be largerthan a second steering angle of the second beam steering cell locatedclose to the center of the beam steering unit 200.

In this case, a change rate of a height H of the nanopillars 10 includedin the first beam steering cell may be higher than a change rate of aheight H of the nanopillars 10 included in the second beam steeringcell.

Meanwhile, for convenience of description, nanopillars 10 have beendescribed as forming nanopatterns by using only one of above attributesW, P, and H. However, embodiments are not limited thereto, and thenanopillars 10 may form nanopatterns by using more than one of theattributes. For example, the plurality of nanopillars 10 included in thefirst beam steering cell 211 may form nanopatterns on the basis of achange in the width W thereof, and the plurality of nanopillars 10included in the third beam steering cell 213 may form nanopatterns onthe basis of a change in the pitch P therebetween.

Also, the plurality of nanopillars 10 may form nanopatterns on a singlebeam steering cell 210 by using multiple attributes. For example, theplurality of nanopillars 10 included in the first beam steering cell 211may form nanopatterns on the basis of changes in the width W thereof andthe pitch P therebetween.

Meanwhile, although in FIGS. 5 to 7, the plurality of nanopillars 10forming nanopatterns are illustrated as having shapes symmetrical aboutthe center of the array, the nanopatterns may also have asymmetricalshapes. Accordingly, a first steering angle of the first beam steeringcell 211 may be different from a third steering angle of a laser beamemitted from the third beam steering cell 213.

Also, the plurality of nanopillars 10 included in each of the pluralityof beam steering cells 210 may form the same nanopattern. Accordingly,laser beams emitted from the plurality of laser emitting units 100 maybe steered in the same direction.

Meanwhile, although it is illustrated in FIGS. 5 to 7 that a singlenanopattern is formed in each beam steering cell 210, nanopatterns inwhich the same pattern is repeated may also be formed in a single beamsteering cell 210.

Meanwhile, the second beam steering cell 212 may not include thenanopillars 10. Accordingly, a laser beam passing through the secondbeam steering cell 212 may be irradiated in a direction which is thesame as an emission direction in which the laser beam is emitted fromthe laser emitting unit 100.

Hereinafter, beam steering by beam steering cells arranged in the formof a two-dimensional array will be described.

FIG. 8 is a view for describing a beam steering unit according to anembodiment.

Referring to FIG. 8, a beam steering unit 200 may include a plurality ofbeam steering cells 210 and a plurality of nanopillars 10. The beamsteering cells 210 may include first to ninth beam steering cells 211,212, 213, 214, 215, 216, 217, 218, and 219.

The beam steering cells 210 according to an embodiment may be providedin the form of a two-dimensional array. For example, laser emittingunits 100 may be provided in the form of a 3×3 array. The first to ninthbeam steering cells 211, 212, 213, 214, 215, 216, 217, 218, and 219 maybe arranged in the two-dimensional array in a row directioncorresponding to a vertical direction and a column directioncorresponding to a horizontal direction.

The beam steering cells 210 may use a plurality of nanopillars 10forming nanopatterns to steer laser beams emitted from the laseremitting units.

The beam steering cells 210 may steer the laser beams emitted from thelaser emitting units 100 to form laser beams of various shapes.

For example, the beam steering cells 210 may form a laser beam having ashape diverging from the center of the laser emitting unit 100.

The plurality of nanopillars 10 may form nanopatterns on the basis oflocations of the beam steering cells 210. For example, the plurality ofnanopillars 10 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200.Accordingly, laser beams emitted from the laser emitting unit 100 mayhave a shape diverging from the center of the beam steering unit 200.

Referring to FIG. 8, the plurality of nanopillars 10 may formnanopatterns on the basis of locations of the beam steering cells 210.

For example, a plurality of nanopillars 10 included in the fifth beamsteering cell 215 located at the central portion of the beam steeringunit 200 may have the same size and be disposed at constant pitches.Accordingly, a laser beam steered by the fifth beam steering cell 215may pass the nanopillars 10, which are disposed as above, as it iswithout being refracted by the nanopillars 10.

Meanwhile, the fifth beam steering cell 215 may not include thenanopillars 10. Accordingly, a laser beam emitted from the laseremitting unit 100 may pass through the fifth beam steering cell 215while an emission direction of the laser beam is maintained.

The fourth beam steering cell 214 may be disposed in the same row as thefifth beam steering cell 215 but in a column that is further to the leftthan a column in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the fourth beamsteering cell 214 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the fourth beam steering cell 214may be the same as a direction from the center of the beam steering unit200 toward the fourth beam steering cell 214.

Likewise, a plurality of nanopillars 10 included in the sixth beamsteering cell 216, which is disposed in the same row as the fifth beamsteering cell 215 but in a column that is further to the right than thecolumn in which the fifth beam steering cell 215 is disposed, may form ananopattern in which a width W thereof gradually increases away from thecenter of the beam steering unit 200. Accordingly, a steering directionof the sixth beam steering cell 216 may be the same as a direction fromthe center of the beam steering unit 200 toward the sixth beam steeringcell 216.

Meanwhile, when the fourth beam steering cell 214 and the sixth beamsteering cell 216 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the fourth beam steering cell214 and the sixth beam steering cell 216 may be equal in size.

The second beam steering cell 212 may be disposed in the same column asthe fifth beam steering cell 215 but in a row that is further to the topthan a row in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the second beamsteering cell 212 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the second beam steering cell 212may be the same as a direction from the center of the beam steering unit200 toward the second beam steering cell 212.

Likewise, a plurality of nanopillars 10 included in the eighth beamsteering cell 218, which is disposed in the same column as the fifthbeam steering cell 215 but in a row that is further to the bottom thanthe row in which the fifth beam steering cell 215 is disposed, may forma nanopattern in which a width W thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the eighth beam steering cell 218 may be the same as adirection from the center of the beam steering unit 200 toward theeighth beam steering cell 218.

Meanwhile, when the second beam steering cell 212 and the eighth beamsteering cell 218 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the second beam steering cell212 and the eighth beam steering cell 218 may be equal in size.

The first beam steering cell 211 may be disposed at an upper left sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form ananopattern in which a width W thereof gradually increases away from thecenter of the beam steering unit 200. Accordingly, a steering directionof the first beam steering cell 211 may be the same as a direction fromthe center of the beam steering unit 200 toward the first beam steeringcell 211.

The third beam steering cell 213 may be disposed at an upper right sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the third beam steering cell 213 may form ananopattern in which a width W thereof gradually increases away from thecenter of the beam steering unit 200. Accordingly, a steering directionof the third beam steering cell 213 may be the same as a direction fromthe center of the beam steering unit 200 toward the third beam steeringcell 213.

The seventh beam steering cell 217 may be disposed at a lower left sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the seventh beam steering cell 217 may form ananopattern in which a width W thereof gradually increases away from thecenter of the beam steering unit 200. Accordingly, a steering directionof the seventh beam steering cell 217 may be the same as a directionfrom the center of the beam steering unit 200 toward the seventh beamsteering cell 217.

The ninth beam steering cell 219 may be disposed at a lower right sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the ninth beam steering cell 219 may form ananopattern in which a width W thereof gradually increases away from thecenter of the beam steering unit 200. Accordingly, a steering directionof the ninth beam steering cell 219 may be the same as a direction fromthe center of the beam steering unit 200 toward the ninth beam steeringcell 219.

Meanwhile, nanopatterns formed by the plurality of nanopillars 10included in the beam steering cells 210, which are spaced apart from thecenter of the beam steering unit 200 at equal distances, may be relatedto each other.

For example, the first beam steering cell 211 and the third beamsteering cell 213 may be spaced apart from the center of the beamsteering unit 200 at equal distances. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form afirst nanopattern. Also, the plurality of nanopillars 10 included in thethird beam steering cell 213 may form a third nanopattern.

In this case, when the first nanopattern is rotated by a predeterminedangle about the center of the beam steering unit 200 as an axis, thefirst nanopattern and the third nanopattern may have the same shape. Thepredetermined angle may be obtained on the basis of locations of thefirst beam steering cell 211 and the third beam steering cell 213relative to the center of the beam steering unit 200.

Meanwhile, a beam steering unit 200 according to another embodiment maysteer a laser beam on the basis of a change in a pitch P betweennanopillars 10, i.e., the number of nanopillars 10 per unit length.

FIG. 9 is a view for describing a beam steering unit according toanother embodiment.

Referring to FIG. 9, a beam steering unit 200 may include a plurality ofbeam steering cells 210 and a plurality of nanopillars 10. The beamsteering cells 210 may include first to ninth beam steering cells 211,212, 213, 214, 215, 216, 217, 218, and 219.

The beam steering cells 210 according to an embodiment may be providedin the form of a two-dimensional array. For example, laser emittingunits 100 may be provided in the form of a 3×3 array. The first to ninthbeam steering cells 211, 212, 213, 214, 215, 216, 217, 218, and 219 maybe arranged in the two-dimensional array in a row directioncorresponding to the vertical direction and a column directioncorresponding to the horizontal direction.

The plurality of nanopillars 10 may form nanopatterns on the basis oflocations of the beam steering cells 210. For example, the plurality ofnanopillars 10 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200.Alternatively, the plurality of nanopillars 10 may form a nanopattern inwhich the number of nanopillars 10 per unit length gradually increasesaway from the center of the beam steering unit 200. Accordingly, a laserbeam emitted from the laser emitting unit 100 may have a shape divergingfrom the center of the beam steering unit 200.

Referring to FIG. 9, the plurality of nanopillars 10 may formnanopatterns on the basis of locations of the beam steering cells 210.

For example, a plurality of nanopillars 10 included in the fifth beamsteering cell 215 located at the central portion of the beam steeringunit 200 may have the same size and be disposed at constant pitches.Accordingly, a laser beam steered by the fifth beam steering cell 215may pass the nanopillars 10, which are disposed as above, as it iswithout being refracted by the nanopillars 10.

Meanwhile, the fifth beam steering cell 215 may not include thenanopillars 10. Accordingly, a laser beam emitted from the laseremitting unit 100 may pass through the fifth beam steering cell 215while an emission direction of the laser beam is maintained.

The fourth beam steering cell 214 may be disposed in the same row as thefifth beam steering cell 215 but in a column that is further to the leftthan a column in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the fourth beamsteering cell 214 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200.Accordingly, a steering direction of the fourth beam steering cell 214may be the same as a direction from the center of the beam steering unit200 toward the fourth beam steering cell 214.

Likewise, a plurality of nanopillars 10 included in the sixth beamsteering cell 216, which is disposed in the same row as the fifth beamsteering cell 215 but in a column that is further to the right than thecolumn in which the fifth beam steering cell 215 is disposed, may form ananopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the sixth beam steering cell 216 may be the same as adirection from the center of the beam steering unit 200 toward the sixthbeam steering cell 216.

Meanwhile, when the fourth beam steering cell 214 and the sixth beamsteering cell 216 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the fourth beam steering cell214 and the sixth beam steering cell 216 may be equal in size.

The second beam steering cell 212 may be disposed in the same column asthe fifth beam steering cell 215 but in a row that is further to the topthan a row in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the second beamsteering cell 212 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200.Accordingly, a steering direction of the second beam steering cell 212may be the same as a direction from the center of the beam steering unit200 toward the second beam steering cell 212.

Likewise, a plurality of nanopillars 10 included in the eighth beamsteering cell 218, which is disposed in the same column as the fifthbeam steering cell 215 but in a row that is further to the bottom thanthe row in which the fifth beam steering cell 215 is disposed, may forma nanopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the eighth beam steering cell 218 may be the same as adirection from the center of the beam steering unit 200 toward theeighth beam steering cell 218.

Meanwhile, when the second beam steering cell 212 and the eighth beamsteering cell 218 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the second beam steering cell212 and the eighth beam steering cell 218 may be equal in size.

The first beam steering cell 211 may be disposed at an upper left sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form ananopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the first beam steering cell 211 may be the same as adirection from the center of the beam steering unit 200 toward the firstbeam steering cell 211.

The third beam steering cell 213 may be disposed at an upper right sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the third beam steering cell 213 may form ananopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the third beam steering cell 213 may be the same as adirection from the center of the beam steering unit 200 toward the thirdbeam steering cell 213.

The seventh beam steering cell 217 may be disposed at a lower left sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the seventh beam steering cell 217 may form ananopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the seventh beam steering cell 217 may be the same as adirection from the center of the beam steering unit 200 toward theseventh beam steering cell 217.

The ninth beam steering cell 219 may be disposed at a lower right sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the ninth beam steering cell 219 may form ananopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the ninth beam steering cell 219 may be the same as adirection from the center of the beam steering unit 200 toward the ninthbeam steering cell 219.

Meanwhile, nanopatterns formed by the plurality of nanopillars 10included in the beam steering cells 210, which are spaced apart from thecenter of the beam steering unit 200 at equal distances, may be relatedto each other.

For example, the first beam steering cell 211 and the third beamsteering cell 213 may be spaced apart from the center of the beamsteering unit 200 at equal distances. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form afirst nanopattern. Also, the plurality of nanopillars 10 included in thethird beam steering cell 213 may form a third nanopattern.

In this case, when the first nanopattern is rotated by a predeterminedangle about the center of the beam steering unit 200 as an axis, thefirst nanopattern and the third nanopattern may have the same shape. Thepredetermined angle may be obtained on the basis of locations of thefirst beam steering cell 211 and the third beam steering cell 213relative to the center of the beam steering unit 200.

Meanwhile, a beam steering unit 200 according to still anotherembodiment may steer a laser beam on the basis of a change in a height Hof the nanopillars 10.

FIG. 10 is a view for describing a beam steering unit according to stillanother embodiment.

Referring to FIG. 10, a beam steering unit 200 may include a pluralityof beam steering cells 210 and a plurality of nanopillars 10. The beamsteering cells 210 may include first to ninth beam steering cells 211,212, 213, 214, 215, 216, 217, 218, and 219.

The beam steering cells 210 according to an embodiment may be providedin the form of a two-dimensional array. For example, laser emittingunits 100 may be provided in the form of a 3×3 array. The first to ninthbeam steering cells 211, 212, 213, 214, 215, 216, 217, 218, and 219 maybe arranged in the two-dimensional array in a row directioncorresponding to the vertical direction and a column directioncorresponding to the horizontal direction.

The plurality of nanopillars 10 may form nanopatterns on the basis oflocations of the beam steering cells 210. For example, the plurality ofnanopillars 10 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200.Accordingly, laser beams emitted from the laser emitting unit 100 mayhave a shape diverging from the center of the beam steering unit 200.

As illustrated in FIG. 10, first to eighth heights H1, H2, H3, H4, H5,H6, H7, and H8 may have values gradually increasing from the firstheight H1 to the eighth height H8.

Referring to FIG. 10, the plurality of nanopillars 10 may formnanopatterns on the basis of locations of the beam steering cells 210.

For example, a plurality of nanopillars 10 included in the fifth beamsteering cell 215 located at the central portion of the beam steeringunit 200 may have the same size and be disposed at constant pitches.Accordingly, a laser beam steered by the fifth beam steering cell 215may pass the nanopillars 10, which are disposed as above, as it iswithout being refracted by the nanopillars 10.

Meanwhile, the fifth beam steering cell 215 may not include thenanopillars 10. Accordingly, a laser beam emitted from the laseremitting unit 100 may pass through the fifth beam steering cell 215while an emission direction of the laser beam is maintained.

The fourth beam steering cell 214 may be disposed in the same row as thefifth beam steering cell 215 but in a column that is further to the leftthan a column in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the fourth beamsteering cell 214 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the fourth beam steering cell 214may be the same as a direction from the center of the beam steering unit200 toward the fourth beam steering cell 214.

Likewise, a plurality of nanopillars 10 included in the sixth beamsteering cell 216, which is disposed in the same row as the fifth beamsteering cell 215 but in a column that is further to the right than thecolumn in which the fifth beam steering cell 215 is disposed, may form ananopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the sixth beam steering cell 216 may be the same as adirection from the center of the beam steering unit 200 toward the sixthbeam steering cell 216.

Meanwhile, when the fourth beam steering cell 214 and the sixth beamsteering cell 216 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the fourth beam steering cell214 and the sixth beam steering cell 216 may be equal in size.

The second beam steering cell 212 may be disposed in the same column asthe fifth beam steering cell 215 but in a row that is further to the topthan a row in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the second beamsteering cell 212 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the second beam steering cell 212may be the same as a direction from the center of the beam steering unit200 toward the second beam steering cell 212.

Likewise, a plurality of nanopillars 10 included in the eighth beamsteering cell 218, which is disposed in the same column as the fifthbeam steering cell 215 but in a row that is further to the bottom thanthe row in which the fifth beam steering cell 215 is disposed, may forma nanopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the eighth beam steering cell 218 may be the same as adirection from the center of the beam steering unit 200 toward theeighth beam steering cell 218.

Meanwhile, when the second beam steering cell 212 and the eighth beamsteering cell 218 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the second beam steering cell212 and the eighth beam steering cell 218 may be equal in size.

The first beam steering cell 211 may be disposed at an upper left sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form ananopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the first beam steering cell 211 may be the same as adirection from the center of the beam steering unit 200 toward the firstbeam steering cell 211.

The third beam steering cell 213 may be disposed at an upper right sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the third beam steering cell 213 may form ananopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the third beam steering cell 213 may be the same as adirection from the center of the beam steering unit 200 toward the thirdbeam steering cell 213.

The seventh beam steering cell 217 may be disposed at a lower left sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the seventh beam steering cell 217 may form ananopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the seventh beam steering cell 217 may be the same as adirection from the center of the beam steering unit 200 toward theseventh beam steering cell 217.

The ninth beam steering cell 219 may be disposed at a lower right sideof the fifth beam steering cell 215. In this case, the plurality ofnanopillars 10 included in the ninth beam steering cell 219 may form ananopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the ninth beam steering cell 219 may be the same as adirection from the center of the beam steering unit 200 toward the ninthbeam steering cell 219.

Meanwhile, nanopatterns formed by the plurality of nanopillars 10included in the beam steering cells 210, which are spaced apart from thecenter of the beam steering unit 200 at equal distances, may be relatedto each other.

For example, the first beam steering cell 211 and the third beamsteering cell 213 may be spaced apart from the center of the beamsteering unit 200 at equal distances. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form afirst nanopattern. Also, the plurality of nanopillars 10 included in thethird beam steering cell 213 may form a third nanopattern.

In this case, when the first nanopattern is rotated by a predeterminedangle about the center of the beam steering unit 200 as an axis, thefirst nanopattern and the third nanopattern may have the same shape. Thepredetermined angle may be obtained on the basis of locations of thefirst beam steering cell 211 and the third beam steering cell 213relative to the center of the beam steering unit 200.

Meanwhile, for convenience of description, nanopatterns formed on thebasis of any one attribute of the width W, pitch P, and height H havebeen described above with reference to FIGS. 8 to 10.

Hereinafter, nanopatterns formed on the basis of multiple attributeswill be described. FIG. 11 is a view for describing a beam steering unitaccording to yet another embodiment.

Referring to FIG. 11, a beam steering unit 200 may include a pluralityof beam steering cells 210 and a plurality of nanopillars 10. The beamsteering cells 210 may include first to ninth beam steering cells 211,212, 213, 214, 215, 216, 217, 218, and 219. The beam steering cells 210according to an embodiment may be provided in the form of atwo-dimensional array. For example, laser emitting units 100 may beprovided in the form of a 3×3 array. The first to ninth beam steeringcells 211, 212, 213, 214, 215, 216, 217, 218, and 219 may be arranged inthe two-dimensional array in a row direction corresponding to thevertical direction and a column direction corresponding to thehorizontal direction.

The plurality of nanopillars 10 included in the beam steering cells 210may form nanopatterns on the basis of a width W and a pitch P.Specifically, the plurality of nanopillars 10 may form nanopatterns onthe basis of the width W in the row direction and on the basis of thepitch P in the column direction.

The plurality of nanopillars 10 may form nanopatterns on the basis oflocations of the beam steering cells 210.

For example, the plurality of nanopillars 10 may form a nanopattern inwhich the width W of the plurality of nanopillars 10 gradually increasesin a direction from the center of the beam steering unit 200 toward alocation of a row in which the beam steering cell 210 including theplurality of nanopillars 10 is included.

Also, the plurality of nanopillars 10 may form a nanopattern in whichthe pitch P between the plurality of nanopillars 10 gradually decreasesin a direction from the center of the beam steering unit 200 toward alocation of a column in which the beam steering cell 210 including theplurality of nanopillars 10 is included. That is, the plurality ofnanopillars 10 may form a nanopattern in which the number of nanopillars10 per unit length gradually increases in a direction from the center ofthe beam steering unit 200 toward a location of a column in which thebeam steering cell 210 including the plurality of nanopillars 10 isincluded.

For example, a plurality of nanopillars 10 included in the fifth beamsteering cell 215 located at the central portion of the beam steeringunit 200 may have the same size and be disposed at constant pitches.Accordingly, a laser beam steered by the fifth beam steering cell 215may pass the nanopillars 10, which are disposed as above, as it iswithout being refracted by the nanopillars 10.

Meanwhile, the fifth beam steering cell 215 may not include thenanopillars 10. Accordingly, a laser beam emitted from the laseremitting unit 100 may pass through the fifth beam steering cell 215while an emission direction of the laser beam is maintained.

The fourth beam steering cell 214 may be disposed in the same row as thefifth beam steering cell 215 but in a column that is further to the leftthan a column in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the fourth beamsteering cell 214 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200.Accordingly, a steering direction of the fourth beam steering cell 214may be the same as a direction from the center of the beam steering unit200 toward the fourth beam steering cell 214.

Likewise, a plurality of nanopillars 10 included in the sixth beamsteering cell 216, which is disposed in the same row as the fifth beamsteering cell 215 but in a column that is further to the right than thecolumn in which the fifth beam steering cell 215 is disposed, may form ananopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the sixth beam steering cell 216 may be the same as adirection from the center of the beam steering unit 200 toward the sixthbeam steering cell 216.

Meanwhile, when the fourth beam steering cell 214 and the sixth beamsteering cell 216 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the fourth beam steering cell214 and the sixth beam steering cell 216 may be equal in size.

The second beam steering cell 212 may be disposed in the same column asthe fifth beam steering cell 215 but in a row that is further to the topthan a row in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the second beamsteering cell 212 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the second beam steering cell 212may be the same as a direction from the center of the beam steering unit200 toward the second beam steering cell 212.

Likewise, a plurality of nanopillars 10 included in the eighth beamsteering cell 218, which is disposed in the same column as the fifthbeam steering cell 215 but in a row that is further to the bottom thanthe row in which the fifth beam steering cell 215 is disposed, may forma nanopattern in which a width W thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the eighth beam steering cell 218 may be the same as adirection from the center of the beam steering unit 200 toward theeighth beam steering cell 218.

Meanwhile, when the second beam steering cell 212 and the eighth beamsteering cell 218 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the second beam steering cell212 and the eighth beam steering cell 218 may be equal in size.

The first beam steering cell 211 may be disposed at an upper left sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the first beamsteering cell 211 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the first beamsteering cell 211 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the first beam steering cell 211may be the same as a direction from the center of the beam steering unit200 toward the first beam steering cell 211.

The third beam steering cell 213 may be disposed at an upper right sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the third beamsteering cell 213 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the third beamsteering cell 213 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the third beam steering cell 213may be the same as a direction from the center of the beam steering unit200 toward the third beam steering cell 213.

The seventh beam steering cell 217 may be disposed at a lower left sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the seventhbeam steering cell 217 may form a nanopattern in which a pitch Ptherebetween gradually decreases away from the center of the beamsteering unit 200 in the column direction.

Also, the plurality of nanopillars 10 included in the seventh beamsteering cell 217 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the seventh beam steering cell 217may be the same as a direction from the center of the beam steering unit200 toward the seventh beam steering cell 217.

The ninth beam steering cell 219 may be disposed at a lower right sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the ninth beamsteering cell 219 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the ninth beamsteering cell 219 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the ninth beam steering cell 219may be the same as a direction from the center of the beam steering unit200 toward the ninth beam steering cell 219.

Meanwhile, nanopatterns formed by the plurality of nanopillars 10included in the beam steering cells 210, which are spaced apart from thecenter of the beam steering unit 200 at equal distances, may be relatedto each other.

For example, the first beam steering cell 211 and the third beamsteering cell 213 may be spaced apart from the center of the beamsteering unit 200 at equal distances. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form afirst nanopattern. Also, the plurality of nanopillars 10 included in thethird beam steering cell 213 may form a third nanopattern.

In this case, when the first nanopattern is rotated by a predeterminedangle about the center of the beam steering unit 200 as an axis, thefirst nanopattern and the third nanopattern may have the same shape. Thepredetermined angle may be obtained on the basis of locations of thefirst beam steering cell 211 and the third beam steering cell 213relative to the center of the beam steering unit 200.

Meanwhile, unlike in FIG. 11, the plurality of nanopillars 10 may formnanopatterns on the basis of the pitch P in the row direction and on thebasis of the width W in the column direction.

FIG. 12 is a view for describing a beam steering unit according to yetanother embodiment.

Referring to FIG. 12, a beam steering unit 200 may include a pluralityof beam steering cells 210 and a plurality of nanopillars 10. The beamsteering cells 210 may include first to ninth beam steering cells 211,212, 213, 214, 215, 216, 217, 218, and 219.

The beam steering cells 210 according to an embodiment may be providedin the form of a two-dimensional array. For example, laser emittingunits 100 may be provided in the form of a 3×3 array. The first to ninthbeam steering cells 211, 212, 213, 214, 215, 216, 217, 218, and 219 maybe arranged in the two-dimensional array in a row directioncorresponding to the vertical direction and a column directioncorresponding to the horizontal direction.

The plurality of nanopillars 10 included in the beam steering cells 210may form nanopatterns on the basis of a width W and a height H.Specifically, the plurality of nanopillars 10 may form nanopatterns onthe basis of the width W in the row direction and on the basis of theheight H in the column direction.

The plurality of nanopillars 10 may form nanopatterns on the basis oflocations of the beam steering cells 210.

For example, the plurality of nanopillars 10 may form a nanopattern inwhich the width W of the plurality of nanopillars 10 gradually increasesin a direction from the center of the beam steering unit 200 toward alocation of a row in which the beam steering cell 210 including theplurality of nanopillars 10 is included.

Also, the plurality of nanopillars 10 may form a nanopattern in whichthe height H of the plurality of nanopillars 10 gradually increases in adirection from the center of the beam steering unit 200 toward alocation of a column in which the beam steering cell 210 including theplurality of nanopillars 10 is included.

For example, a plurality of nanopillars 10 included in the fifth beamsteering cell 215 located at the central portion of the beam steeringunit 200 may have the same size and be disposed at constant pitches.Accordingly, a laser beam steered by the fifth beam steering cell 215may pass the nanopillars 10, which are disposed as above, as it iswithout being refracted by the nanopillars 10.

Meanwhile, the fifth beam steering cell 215 may not include thenanopillars 10. Accordingly, a laser beam emitted from the laseremitting unit 100 may pass through the fifth beam steering cell 215while an emission direction of the laser beam is maintained.

The fourth beam steering cell 214 may be disposed in the same row as thefifth beam steering cell 215 but in a column that is further to the leftthan a column in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the fourth beamsteering cell 214 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the fourth beam steering cell 214may be the same as a direction from the center of the beam steering unit200 toward the fourth beam steering cell 214.

Likewise, a plurality of nanopillars 10 included in the sixth beamsteering cell 216, which is disposed in the same row as the fifth beamsteering cell 215 but in a column that is further to the right than thecolumn in which the fifth beam steering cell 215 is disposed, may form ananopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the sixth beam steering cell 216 may be the same as adirection from the center of the beam steering unit 200 toward the sixthbeam steering cell 216.

Meanwhile, when the fourth beam steering cell 214 and the sixth beamsteering cell 216 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the fourth beam steering cell214 and the sixth beam steering cell 216 may be equal in size.

The second beam steering cell 212 may be disposed in the same column asthe fifth beam steering cell 215 but in a row that is further to the topthan a row in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the second beamsteering cell 212 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the second beam steering cell 212may be the same as a direction from the center of the beam steering unit200 toward the second beam steering cell 212.

Likewise, a plurality of nanopillars 10 included in the eighth beamsteering cell 218, which is disposed in the same column as the fifthbeam steering cell 215 but in a row that is further to the bottom thanthe row in which the fifth beam steering cell 215 is disposed, may forma nanopattern in which a width W thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the eighth beam steering cell 218 may be the same as adirection from the center of the beam steering unit 200 toward theeighth beam steering cell 218.

Meanwhile, when the second beam steering cell 212 and the eighth beamsteering cell 218 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the second beam steering cell212 and the eighth beam steering cell 218 may be equal in size.

The first beam steering cell 211 may be disposed at an upper left sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the first beamsteering cell 211 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the first beamsteering cell 211 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the first beam steering cell 211may be the same as a direction from the center of the beam steering unit200 toward the first beam steering cell 211.

The third beam steering cell 213 may be disposed at an upper right sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the third beamsteering cell 213 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the third beamsteering cell 213 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the third beam steering cell 213may be the same as a direction from the center of the beam steering unit200 toward the third beam steering cell 213.

The seventh beam steering cell 217 may be disposed at a lower left sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the seventhbeam steering cell 217 may form a nanopattern in which a height Hthereof gradually increases away from the center of the beam steeringunit 200 in the column direction.

Also, the plurality of nanopillars 10 included in the seventh beamsteering cell 217 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the seventh beam steering cell 217may be the same as a direction from the center of the beam steering unit200 toward the seventh beam steering cell 217.

The ninth beam steering cell 219 may be disposed at a lower right sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the ninth beamsteering cell 219 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the ninth beamsteering cell 219 may form a nanopattern in which a width W thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the ninth beam steering cell 219may be the same as a direction from the center of the beam steering unit200 toward the ninth beam steering cell 219.

Meanwhile, nanopatterns formed by the plurality of nanopillars 10included in the beam steering cells 210, which are spaced apart from thecenter of the beam steering unit 200 at equal distances, may be relatedto each other.

For example, the first beam steering cell 211 and the third beamsteering cell 213 may be spaced apart from the center of the beamsteering unit 200 at equal distances. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form afirst nanopattern. Also, the plurality of nanopillars 10 included in thethird beam steering cell 213 may form a third nanopattern.

In this case, when the first nanopattern is rotated by a predeterminedangle about the center of the beam steering unit 200 as an axis, thefirst nanopattern and the third nanopattern may have the same shape. Thepredetermined angle may be obtained on the basis of locations of thefirst beam steering cell 211 and the third beam steering cell 213relative to the center of the beam steering unit 200.

Meanwhile, unlike in FIG. 12, the plurality of nanopillars 10 may formnanopatterns on the basis of the height H in the row direction and onthe basis of the width W in the column direction.

FIG. 13 is a view for describing a beam steering unit according to yetanother embodiment.

Referring to FIG. 13, a beam steering unit 200 may include a pluralityof beam steering cells 210 and a plurality of nanopillars 10. The beamsteering cells 210 may include first to ninth beam steering cells 211,212, 213, 214, 215, 216, 217, 218, and 219.

The beam steering cells 210 according to an embodiment may be providedin the form of a two-dimensional array. For example, laser emittingunits 100 may be provided in the form of a 3×3 array. The first to ninthbeam steering cells 211, 212, 213, 214, 215, 216, 217, 218, and 219 maybe arranged in the two-dimensional array in a row directioncorresponding to the vertical direction and a column directioncorresponding to the horizontal direction.

The plurality of nanopillars 10 included in the beam steering cells 210may form nanopatterns on the basis of a pitch P and a height H.Specifically, the plurality of nanopillars 10 may form nanopatterns onthe basis of the height H in the row direction and on the basis of thepitch P in the column direction.

The plurality of nanopillars 10 may form nanopatterns on the basis oflocations of the beam steering cells 210.

For example, the plurality of nanopillars 10 may form a nanopattern inwhich the height H of the plurality of nanopillars 10 graduallyincreases in a direction from the center of the beam steering unit 200toward a location of a row in which the beam steering cell 210 includingthe plurality of nanopillars 10 is included.

Also, the plurality of nanopillars 10 may form a nanopattern in whichthe pitch P between the plurality of nanopillars 10 gradually decreasesin a direction from the center of the beam steering unit 200 toward alocation of a column in which the beam steering cell 210 including theplurality of nanopillars 10 is included.

For example, a plurality of nanopillars 10 included in the fifth beamsteering cell 215 located at the central portion of the beam steeringunit 200 may have the same size and be disposed at constant pitches.Accordingly, a laser beam steered by the fifth beam steering cell 215may pass the nanopillars 10, which are disposed as above, as it iswithout being refracted by the nanopillars 10.

Meanwhile, the fifth beam steering cell 215 may not include thenanopillars 10. Accordingly, a laser beam emitted from the laseremitting unit 100 may pass through the fifth beam steering cell 215while an emission direction of the laser beam is maintained.

The fourth beam steering cell 214 may be disposed in the same row as thefifth beam steering cell 215 but in a column that is further to the leftthan a column in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the fourth beamsteering cell 214 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200.Accordingly, a steering direction of the fourth beam steering cell 214may be the same as a direction from the center of the beam steering unit200 toward the fourth beam steering cell 214.

Likewise, a plurality of nanopillars 10 included in the sixth beamsteering cell 216, which is disposed in the same row as the fifth beamsteering cell 215 but in a column that is further to the right than thecolumn in which the fifth beam steering cell 215 is disposed, may form ananopattern in which a pitch P therebetween gradually decreases awayfrom the center of the beam steering unit 200. Accordingly, a steeringdirection of the sixth beam steering cell 216 may be the same as adirection from the center of the beam steering unit 200 toward the sixthbeam steering cell 216.

Meanwhile, when the fourth beam steering cell 214 and the sixth beamsteering cell 216 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the fourth beam steering cell214 and the sixth beam steering cell 216 may be equal in size.

The second beam steering cell 212 may be disposed in the same column asthe fifth beam steering cell 215 but in a row that is further to the topthan a row in which the fifth beam steering cell 215 is disposed. Inthis case, a plurality of nanopillars 10 included in the second beamsteering cell 212 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200.Accordingly, a steering direction of the second beam steering cell 212may be the same as a direction from the center of the beam steering unit200 toward the second beam steering cell 212.

Likewise, a plurality of nanopillars 10 included in the eighth beamsteering cell 218, which is disposed in the same column as the fifthbeam steering cell 215 but in a row that is further to the bottom thanthe row in which the fifth beam steering cell 215 is disposed, may forma nanopattern in which a height H thereof gradually increases away fromthe center of the beam steering unit 200. Accordingly, a steeringdirection of the eighth beam steering cell 218 may be the same as adirection from the center of the beam steering unit 200 toward theeighth beam steering cell 218.

Meanwhile, when the second beam steering cell 212 and the eighth beamsteering cell 218 are disposed to be symmetrical about the center of thebeam steering unit 200, steering angles of the second beam steering cell212 and the eighth beam steering cell 218 may be equal in size.

The first beam steering cell 211 may be disposed at an upper left sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the first beamsteering cell 211 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the first beamsteering cell 211 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the first beam steering cell 211may be the same as a direction from the center of the beam steering unit200 toward the first beam steering cell 211.

The third beam steering cell 213 may be disposed at an upper right sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the third beamsteering cell 213 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the third beamsteering cell 213 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the third beam steering cell 213may be the same as a direction from the center of the beam steering unit200 toward the third beam steering cell 213.

The seventh beam steering cell 217 may be disposed at a lower left sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the seventhbeam steering cell 217 may form a nanopattern in which a pitch Ptherebetween gradually decreases away from the center of the beamsteering unit 200 in the column direction.

Also, the plurality of nanopillars 10 included in the seventh beamsteering cell 217 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the seventh beam steering cell 217may be the same as a direction from the center of the beam steering unit200 toward the seventh beam steering cell 217.

The ninth beam steering cell 219 may be disposed at a lower right sideof the fifth beam steering cell 215.

In this case, the plurality of nanopillars 10 included in the ninth beamsteering cell 219 may form a nanopattern in which a pitch P therebetweengradually decreases away from the center of the beam steering unit 200in the column direction.

Also, the plurality of nanopillars 10 included in the ninth beamsteering cell 219 may form a nanopattern in which a height H thereofgradually increases away from the center of the beam steering unit 200in the row direction.

Accordingly, a steering direction of the ninth beam steering cell 219may be the same as a direction from the center of the beam steering unit200 toward the ninth beam steering cell 219.

Meanwhile, nanopatterns formed by the plurality of nanopillars 10included in the beam steering cells 210, which are spaced apart from thecenter of the beam steering unit 200 at equal distances, may be relatedto each other.

For example, the first beam steering cell 211 and the third beamsteering cell 213 may be spaced apart from the center of the beamsteering unit 200 at equal distances. In this case, the plurality ofnanopillars 10 included in the first beam steering cell 211 may form afirst nanopattern. Also, the plurality of nanopillars 10 included in thethird beam steering cell 213 may form a third nanopattern.

In this case, when the first nanopattern is rotated by a predeterminedangle about the center of the beam steering unit 200 as an axis, thefirst nanopattern and the third nanopattern may have the same shape. Thepredetermined angle may be obtained on the basis of locations of thefirst beam steering cell 211 and the third beam steering cell 213relative to the center of the beam steering unit 200.

Meanwhile, unlike in FIG. 13, the plurality of nanopillars 10 may formnanopatterns on the basis of the pitch P in the row direction and on thebasis of the height H in the column direction.

FIG. 14 is a top view for describing a beam steering unit according toan embodiment.

Referring to FIG. 14, a beam steering unit 200 according to anembodiment may include a plurality of beam steering cells 210 and aplurality of nanopillars 10. The beam steering cells 210 may includefirst to ninth beam steering cells 211, 212, 213, 214, 215, 216, 217,218, and 219.

The beam steering cells 210 according to an embodiment may be providedin the form of a two-dimensional array. For example, laser emittingunits 100 may be provided in the form of a 3×3 array. The first to ninthbeam steering cells 211, 212, 213, 214, 215, 216, 217, 218, and 219 maybe arranged in the two-dimensional array in a row directioncorresponding to the vertical direction and a column directioncorresponding to the horizontal direction.

A plurality of laser emitting units 100 may be disposed at a lowerportion of at least one of the plurality of beam steering cells 210.

For example, first to fourth laser emitting units 101, 102, 103, and 104may be disposed at a lower portion of the third beam steering cell 213.

The first to fourth laser emitting units 101, 102, 103, and 104 may becontrolled separately.

Attributes of a laser beam emitted from the first laser emitting unit101 and attributes of a laser beam emitted from the second laseremitting unit 102 may be different.

For example, a wavelength of a laser beam emitted from the first laseremitting unit 101 and a wavelength of a laser beam emitted from thesecond laser emitting unit 102 may be different.

As another example, an intensity of a laser beam emitted from the firstlaser emitting unit 101 and an intensity of a laser beam emitted fromthe second laser emitting unit 102 may be different.

As still another example, laser beam emission time points of the firstlaser emitting unit 101 and the second laser emitting unit 102 may bedifferent. Specifically, while the first laser emitting unit 101 emits alaser beam, the second laser emitting unit 102 may be turned off.

Meanwhile, the plurality of nanopillars 10 included in the beam steeringcells 210 may form a plurality of nanopatterns. For example, theplurality of nanopatterns may include a first nanopattern A1 and asecond nanopattern A2.

At least one of the plurality of nanopatterns may be repeatedly formedon the beam steering cell 210. For example, a plurality of nanopillars10 included in the sixth beam steering cell 216 of FIG. 14 mayrepeatedly form the first nanopattern A1. Specifically, the firstnanopattern A1 may have a pattern in which the width W of thenanopillars 10 repeatedly increases.

The second nanopattern A2 may have a different form from the firstnanopattern A1. For example, the first nanopattern A1 may have a form inwhich the width W of the nanopillars 10 gradually increases away fromthe center of the beam steering unit 200 while the width W of thenanopillars is constant in the row direction. On the other hand, thesecond nanopattern A2 may have a form in which the width W of thenanopillars 10 gradually increases away from the center of the beamsteering unit 200 while the width W of the nanopillars 10 changes in therow direction.

Meanwhile, by the on/off state of each laser emitting unit beingadjusted, laser beams of various shapes may be formed. For example, theshape of a laser beam emitted from the laser emitting device 1000 mayvary according to the on/off states of the first laser emitting unit 101and the second laser emitting unit 102.

By the on/off states of a plurality of light source units included inthe laser emitting unit being adjusted, laser beams of various shapesmay be formed. For example, the shape of a laser beam which is emittedfrom the third laser emitting unit 103 and passes the nanopillars 10 mayvary according to the on/off states of a first light source unit and asecond light source unit included in the third laser emitting unit 103.

By an intensity of a laser beam emitted from each laser emitting unitbeing adjusted, laser beams of various shapes may be formed. Forexample, the shape of a laser beam emitted from the laser emittingdevice 1000 may vary as intensities of laser beams emitted from thefirst laser emitting unit 101 and the second laser emitting unit 102 areadjusted.

By an intensity of a laser beam emitted from a plurality of light sourceunits included in the laser emitting unit being adjusted, laser beams ofvarious shapes may be formed. For example, the shape of a laser beamwhich is emitted from the third laser emitting unit 103 and passes thenanopillars 10 may vary as intensities of laser beams emitted from afirst light source unit 1131 and a second light source unit 1132 areadjusted.

Meanwhile, the nanopatterns have been described above as being formedfor each beam steering cell 210 as a unit, but the nanopatterns may alsobe formed in the entire beam steering unit 200 regardless of boundariesof the plurality of beam steering cells 210. Accordingly, thenanopillars 10 may be disposed on a boundary line between two adjacentbeam steering cells 210.

The number of nanopillars 10 disposed on each beam steering cell 210 maybe different.

For convenience of description, the case in which the beam steering unit200 is provided as a 3×3 array, i.e., an N×N array, has been describedabove as an example, but the beam steering unit 200 may also be providedas an N×M array (here, the N and M are different numbers).

FIG. 15 is a pictorial diagram illustrating a laser beam emitted from alaser emitting device according to an embodiment.

Referring to FIG. 15, a laser emitting device 1000 may include a laseremitting unit 100, a beam steering unit 200, and a plurality ofnanopillars 10. Meanwhile, at least one of the plurality of nanopillars10 illustrated in FIG. 15 may include a plurality of nanostructures. Forexample, the nanopillar 10 may include one or more nanostructure havingan irregular shape.

The laser emitting device 1000 may emit a laser beam toward an object.

The laser emitting device 1000 may generate a plurality of scanningpoints distributed in an h-direction, which is the horizontal direction,and a v-direction, which is the vertical direction. The laser emittingdevice 1000 may have a field of view (FOV) formed by the plurality ofscanning points. For example, the laser emitting device 1000 may havethe FOV in a range of −N° to N° in the h-direction. Also, the laseremitting device 1000 may have the FOV in a range of −M° to M° in thev-direction. Specifically, the laser emitting device 1000 may have theFOV in a range of −60° to 60° in the h-direction and the FOV in a rangeof −15° to 15° in the v-direction.

The N may be greater than the M. That is, the laser emitting device 1000may have the FOV in a wider range in the h-direction than in thev-direction.

Regarding the laser emitting unit 100, since the description given aboveon the laser emitting unit 100 may be applied without change, detaileddescription thereof will be omitted.

The beam steering unit 200 may include a plurality of nanopillars 10.

The beam steering unit 200 may include the plurality of beam steeringcells. The plurality of beam steering cells may be arranged in the formof a two-dimensional array. The plurality of beam steering cells may bearranged in the two-dimensional array in a row direction correspondingto the vertical direction and a column direction corresponding to thehorizontal direction.

Each of the plurality of beam steering cells may include a plurality ofnanopillars 10.

The plurality of beam steering cells may guide a laser beam emitted fromthe laser emitting unit 100 to correspond to the plurality of scanningpoints. In this case, the plurality of beam steering cells may guide thelaser beam using the plurality of nanopillars 10.

Meanwhile, a beam steering surface S1 may be defined as a surfaceincluded in a region in which a laser beam emitted from the laseremitting unit 100 is steered. Specifically, the beam steering surface S1may refer to a cross-section of the beam steering unit 200.

Also, a beam projection surface S2 may be defined as a surface includedin a region in which a laser beam emitted from the laser emitting device1000 is projected to an object.

The beam steering surface S1 may be parallel to the beam projectionsurface S2.

As described above, the plurality of nanopillars 10 included in the beamsteering unit 200 may form nanopatterns on the basis of locations of thebeam steering cells. That is, the plurality of nanopillars 10 may formnanopatterns on the basis of locations thereof on the beam steeringsurface S1.

Unlike this, the plurality of nanopillars 10 may form nanopatterns onthe basis of a steering direction in which the plurality of beamsteering cells guide a laser beam emitted from the laser emitting unit100. That is, the plurality of nanopillars 10 may form nanopatterns onthe basis of locations thereof on the beam projection surface S2.

Hereinafter, the nanopatterns formed on the basis of locations on thebeam steering surface S1 and the beam projection surface S2 will bedescribed.

FIG. 16 is a view illustrating a beam steering unit 200 according to anembodiment.

Specifically, FIG. 16 is a view for describing the nanopatterns formedon the basis of locations on the beam steering surface S1.

The beam steering unit 200 may include first to fourth beam steeringcells 211, 212, 213, and 214. The first to fourth beam steering cells211, 212, 213, and 214 may include a plurality of nanopillars formingnanopatterns.

The first beam steering cell 211 may be arranged at the center of thebeam steering unit 200.

An h-coordinate of the second beam steering cell 212 may be greater thanan h-coordinate of the first beam steering cell 211. In this case, theplurality of nanopillars included in the second beam steering cell 212may form, from the center of the beam steering unit 200 toward thesecond beam steering cell 212, a nanopattern in which a first attributerelated to at least one of the width W, height H, and number per unitlength of the nanopillars repeatedly increases.

A v-coordinate of the third beam steering cell 213 may be greater than av-coordinate of the first beam steering cell 211. In this case, theplurality of nanopillars included in the third beam steering cell 213may form, from the center of the beam steering unit 200 toward the thirdbeam steering cell 213, a nanopattern in which an attribute related toat least one of the width W, height H, and number per unit length of thenanopillars repeatedly increases.

Meanwhile, as a distance from the center of the beam steering unit 200to a beam steering cell becomes larger, a change rate of an attribute ofa plurality of nanopillars included in the beam steering cell mayincrease.

For example, an h-coordinate of the fourth beam steering cell 214 may begreater than an h-coordinate of the second beam steering cell 212.Accordingly, a distance from the center of the beam steering unit 200 tothe fourth beam steering cell 214 may be larger than a distance from thecenter of the beam steering unit 200 to the second beam steering cell212.

In this case, the plurality of nanopillars included in the fourth beamsteering cell 214 may form, from the center of the beam steering unit200 toward the fourth beam steering cell 214, a nanopattern in which asecond attribute related to at least one of the width W, height H, andnumber per unit length of the nanopillars repeatedly increases. A changerate of an attribute may be higher than the change rate of the firstattribute.

FIG. 17 is a view illustrating a beam projection surface S2 according toan embodiment.

Specifically, FIG. 17 is a view for describing the nanopatterns formedon the basis of locations on the beam projection surface S2.

The beam projection surface S2 may be expressed in the form of atwo-dimensional array in the h-direction corresponding to the horizontaldirection and the v-direction corresponding to the vertical direction.

A first projection cell C1 may be located at the center of the beamprojection surface S2. In this case, a first laser beam projected to thefirst projection cell C1 may have been steered by a first beam steeringcell. The plurality of nanopillars included in the first beam steeringcell may form a nanopattern in which a first attribute related to atleast one of the width W, height H, and number per unit length of thenanopillars is the same.

An h-coordinate of a second projection cell C2 may be greater than anh-coordinate of the first projection cell C1. In this case, a secondlaser beam projected to the second projection cell C2 may have beensteered by a second beam steering cell. The plurality of nanopillarsincluded in the second beam steering cell may form, in a direction of anh-axis component of a steering direction of the second beam steeringcell, nanopatterns in which a second attribute related to at least oneof the width W, height H, and number per unit length of the nanopillarsrepeatedly increases.

A v-coordinate of a third projection cell C3 may be greater than av-coordinate of the first projection cell C1. In this case, a thirdlaser beam projected to the third projection cell C3 may have beensteered by a third beam steering cell. The plurality of nanopillarsincluded in the third beam steering cell may form, in a direction of av-axis component of a steering direction of the third beam steeringcell, nanopatterns in which a third attribute related to at least one ofthe width W, height H, and number per unit length of the nanopillarsrepeatedly increases.

Meanwhile, as a location of a cell becomes farther from the center ofthe beam projection surface S2, a change rate of an attribute of aplurality of nanopillars included in a beam steering cell, which steersa laser beam projected to the cell, may increase.

For example, a fourth projection cell C4 may have an h-coordinategreater than that of the first projection cell C1 but may be locatedfarther from the center of the beam projection surface S2 than thesecond projection cell C2. A fourth laser beam projected to the fourthprojection cell C4 may have been steered by a fourth beam steering cell.The plurality of nanopillars included in the fourth beam steering cellmay form, in a direction of an h-axis component of a steering directionof the fourth beam steering cell, nanopatterns in which a fourthattribute related to at least one of the width W, height H, and numberper unit length of the nanopillars repeatedly increases.

In this case, a change rate of the fourth attribute may be higher thanthe change rate of the second attribute.

Meanwhile, such a relationship between the rates of change may remainthe same even when sizes of v-axis components of steering directionschange.

Meanwhile, a location on the beam steering surface S1 may be related toa location on the beam projection surface S2.

For example, a location on the beam steering surface S1 may correspondto a location on the beam projection surface S2.

Specifically, the first to fourth projection cells C1, C2, C3, and C4may respectively correspond to the first to fourth beam steering cells211, 212, 213, and 214 of FIG. 16. That is, a first laser beamirradiated to the first projection cell C1 may have been steered by thefirst beam steering cell 211. The same applies for the second to fourthprojection cells C2, C3, and C4.

Alternatively, a location on the beam steering surface S1 may notcorrespond to a location on the beam projection surface S2.

Specifically, the first to fourth projection cells C1, C2, C3, and C4may not respectively correspond to the first to fourth beam steeringcells 211, 212, 213, and 214. For example, a third laser beam irradiatedto the third projection cell C3 may have been steered by the second beamsteering cell 212.

Meanwhile, referring to FIG. 18, sizes of the plurality of nanopillars10 included in the beam steering unit 200 of the laser emitting device1000 may be the same. For example, widths W and heights H of theplurality of nanopillars 10 may be the same. Alternatively, pitches Pbetween the plurality of nanopillars 10 may be the same.

In this case, a steering angle θ of a laser beam may be 0°. That is, afirst angle, which is an emission angle of a laser beam emitted from thelaser emitting unit 100, may be equal to a second angle, which is anirradiation angle of a laser beam that has passed the beam steering unit200 after being emitted from the laser emitting unit 100.

The laser emitting device 1000 in which the beam steering unit 200 isconfigured of a single layer has been described above.

Hereinafter, a laser emitting device 1000 in which the beam steeringunit 200 is configured of a plurality of layers will be described.

FIG. 19 is a pictorial diagram illustrating a laser emitting deviceaccording to an embodiment.

Referring to FIG. 19, a laser emitting device 1000 may include a laseremitting unit 100 and a beam steering unit 200.

Meanwhile, the laser emitting device 1000 may operate identically orsimilarly to the laser emitting device 1000 described above withreference to FIGS. 1 to 18. Accordingly, detailed description of pointsin common will be omitted, and differences therebetween will be mainlydescribed.

The laser emitting device 1000 may generate laser beams of variousshapes from a laser beam emitted from the laser emitting unit 100 byusing the beam steering unit 200. For example, the laser emitting device1000 may generate a laser beam having a shape diverging from the centerthereof.

Each configuration of the laser emitting device 1000 will be describedin detail below.

The laser emitting unit 100 may operate identically or similarly to thelaser emitting unit 100 described above with reference to FIGS. 1 to 18.For example, the laser emitting unit 100 may be arranged in the form ofan array and include a plurality of VCSEL elements.

The beam steering unit 200 may steer a laser beam emitted from the laseremitting unit 100. The beam steering unit 200 may generate laser beamsof various shapes by steering the emitted laser beam.

For example, the beam steering unit 200 may form, from the emitted laserbeam, a laser beam having an h-direction, which is the horizontaldirection, and a v-direction, which is the vertical direction.

The beam steering unit 200 may include a first beam steering unit 201and a second beam steering unit 202. Each of the first beam steeringunit 201 and the second beam steering unit 202 may include a pluralityof nanopillars 10.

The first beam steering unit 201 may steer a laser beam emitted from thelaser emitting unit 100. The plurality of nanopillars 10 included in thefirst beam steering unit 201 may form a nanopattern. The first beamsteering unit 201 may steer, on the basis of the nanopattern, a laserbeam emitted from the laser emitting unit 100.

The laser beam steered by the first beam steering unit 201 may beprojected toward the second beam steering unit 202.

The second beam steering unit 202 may obtain the laser beam emitted fromthe first beam steering unit 201. The second beam steering unit 202 maysteer the obtained laser beam.

The plurality of nanopillars 10 included in the second beam steeringunit 202 may form a nanopattern. The second beam steering unit 202 maysteer the obtained laser beam on the basis of the nanopattern.

The laser beam steered by the second beam steering unit 202 may beprojected toward an object.

The first beam steering unit 201 may be disposed at an upper portion ofthe laser emitting unit 100. Specifically, the first beam steering unit201 may be disposed at an emission surface side at which a laser beam isemitted from the laser emitting unit 100.

The second beam steering unit 202 may be disposed at an upper portion ofthe first beam steering unit 201.

Accordingly, laser beams emitted from the laser emitting unit 100 maysequentially pass through the first beam steering unit 201 and thesecond beam steering unit 202.

FIG. 20 is an exploded perspective view of a laser emitting deviceaccording to an embodiment.

Referring to FIG. 20, a laser emitting device 1000 may include a laseremitting unit 100 and a beam steering unit 200. The beam steering unit200 may include a first beam steering unit 201 and a second beamsteering unit 202.

The laser emitting device 1000 may generate a plurality of scanningpoints distributed in the horizontal direction and vertical direction.The laser emitting device 1000 may have the FOV formed in the horizontaldirection and the vertical direction.

The laser emitting unit 100 may be disposed at a lower portion of thefirst beam steering unit 201 and may irradiate a laser beam toward thefirst beam steering unit 201. Meanwhile, since the laser emitting unit100 may operate identically or similarly to the laser emitting unit 100described above with reference to FIGS. 1 to 18, detailed descriptionthereof will be omitted.

The first beam steering unit 201 may be disposed at an upper portion ofthe laser emitting unit 100 and obtain a laser beam emitted from thelaser emitting unit 100. The first beam steering unit 201 may generatelaser beams of various shapes by steering the obtained laser beam.

Specifically, the first beam steering unit 201 may steer the obtainedlaser beam using a plurality of nanopillars 10. The first beam steeringunit 201 may include a metasurface.

The first beam steering unit 201 may steer a laser beam in theh-direction corresponding to the horizontal direction and thev-direction corresponding to the vertical direction.

For example, the first beam steering unit 201 may generate a laser beamhaving a shape diverging in the v-direction. A vertical steering angleθv of the first beam steering unit 201 may be in a range of −15° to 15°.Here, the steering angle may refer to an angle in a clockwise directionfrom a virtual reference line which is perpendicular to an emissionsurface. That is, a steering direction having a positive steering anglemay be located at a right side of the reference line, and a steeringdirection having a negative steering angle may be located at a left sideof the reference line.

In this case, the plurality of nanopillars 10 included in the first beamsteering unit 201 may form a subwavelength pattern in which at least oneattribute of the width W, height H, and number per unit lengthrepeatedly increases in the v-direction.

The second beam steering unit 202 may be disposed at an upper portion ofthe first beam steering unit 201 and obtain a laser beam steered by thefirst beam steering unit 201. The second beam steering unit 202 maygenerate laser beams of various shapes by steering the laser beamobtained from the first beam steering unit 201.

Specifically, the second beam steering unit 202 may steer the obtainedlaser beam using a plurality of nanopillars 10. The second beam steeringunit 202 may include a metasurface.

The second beam steering unit 202 may steer a laser beam in theh-direction corresponding to the horizontal direction and thev-direction corresponding to the vertical direction.

For example, the second beam steering unit 202 may generate a laser beamhaving a shape diverging in the h-direction. A horizontal steering angleθh of the second beam steering unit 202 may be in a range of −60° to60°.

In this case, the plurality of nanopillars 10 included in the secondbeam steering unit 202 may form a subwavelength pattern in which atleast one attribute of the width W, height H, and number per unit lengthrepeatedly increases in the h-direction.

Meanwhile, each of the first beam steering unit 201 and the second beamsteering unit 202 may include the plurality of beam steering cellsincluding the plurality of nanopillars 10. The plurality of beamsteering cells may be arranged in the form of an array along the v-axisor h-axis.

In this case, an arrangement direction of the plurality of beam steeringcells included in the first beam steering unit 201 and an arrangementdirection of the plurality of beam steering cells included in the secondbeam steering unit 202 may be different.

For example, the plurality of beam steering cells included in the firstbeam steering unit 201 may be arranged in the form of an array along thev-axis. On the other hand, the plurality of beam steering cells includedin the second beam steering unit 202 may be arranged in the form of anarray along the h-axis.

Meanwhile, although some of the laser beams steered by the first beamsteering unit 201 are seen in FIG. 20 as being projected to the outsideof the second beam steering unit 202, this is merely for convenience ofdescription, and some of the laser beams are not projected to theoutside of the second beam steering unit 202 in reality.

FIGS. 21 to 23 are exploded perspective views of a laser emitting deviceaccording to various embodiments viewed from the side.

Specifically, FIGS. 21 and 22 are exploded perspective views of a laseremitting device viewed along the h-axis. FIG. 23 is an explodedperspective view of a laser emitting device viewed along the v-axis.

Referring to FIG. 21, a laser emitting device 1000 may include a laseremitting unit 100 and a beam steering unit 200. The beam steering unit200 may include a first beam steering unit 201 and a second beamsteering unit 202. Each of the first beam steering unit 201 and thesecond beam steering unit 202 may include a plurality of nanopillars 10.

The laser emitting device 1000 may include a support unit 300 configuredto support the beam steering unit 200.

The support unit 300 may support the nanopillars 10 included in the beamsteering unit 200. Alternatively, the support unit 300 may support ametasurface including the plurality of nanopillars 10. Accordingly, theplurality of nanopillars 10 may be deposited on the support unit 300.

A light transmittance of the support unit 300 may be at least 90% orhigher.

The support unit 300 may be formed of various materials. For example,the support unit 300 may include glass, metamaterial, and the like.

The support unit 300 may be provided in the form of a flat panel.

The support unit 300 may include a first support unit 301 and a secondsupport unit 302.

The first support unit 301 may be disposed between the laser emittingunit 100 and the first beam steering unit 201 to support the first beamsteering unit 201.

The second support unit 302 may be disposed between the first beamsteering unit 201 and the second beam steering unit 202 to support thesecond beam steering unit 202.

The first support unit 301 and the second support unit 302 may be formedof different materials.

A refractive index of the first support unit 301 may be lower than arefractive index of the nanopillars 10 included in the first beamsteering unit 201.

The laser emitting unit 100 may include a plurality of laser emittingunits 101, 102, and 103 arranged in the form of a one-dimensional arrayin the v-direction.

Each of the plurality of laser emitting units 101, 102, and 103 may emita laser beam toward the beam steering unit 200.

The first beam steering unit 201 may obtain a laser beam emitted fromthe laser emitting unit 100.

The first beam steering unit 201 may steer the obtained laser beam usingthe plurality of nanopillars 10.

The first beam steering unit 201 may generate a laser beam having ashape diverging in the v-direction. For example, a vertical steeringangle θv of the first beam steering unit 201 may be in the range of −15°to 15°

In this case, the plurality of nanopillars 10 included in the first beamsteering unit 201 may form a subwavelength pattern in which a width Wthereof increases along the v-axis.

Specifically, the plurality of nanopillars 10 included in the first beamsteering unit 201 may form, in a direction away from the center of thefirst beam steering unit 201 along the v-axis, a nanopattern in whichthe width W thereof increases.

Meanwhile, the first beam steering unit 201 may include a first beamsteering cell 2011, a second beam steering cell 2012, and a third beamsteering cell 2013. A plurality of nanopillars 10 included in each ofthe plurality of beam steering cells 2011, 2012, and 2013 may form ananopattern on the basis of locations of the plurality of beam steeringcells 2011, 2012, and 2013.

For example, the plurality of nanopillars 10 included in the second beamsteering cell 2012 located at the center of the first beam steering unit201 may form a nanopattern in which an attribute related to at least oneof the width W, height H, and number per unit length is uniform.Accordingly, a steering angle of the second beam steering cell 2012 maybe 0°.

In this case, the plurality of nanopillars 10 included in the first beamsteering cell 2011 located at the left of the second beam steering cell2012 may form a nanopattern in which an attribute related to at leastone of the width W, height H, and number per unit length increases in adirection from the center of the first beam steering unit 201 toward thefirst beam steering cell 2011. Accordingly, a vertical steering angle θvof the first beam steering cell 2011 may have a negative value.

Likewise, the plurality of nanopillars 10 included in the third beamsteering cell 2013 located at the right of the second beam steering cell2012 may form a nanopattern in which an attribute related to at leastone of the width W, height H, and number per unit length increases in adirection from the center of the first beam steering unit 201 toward thethird beam steering cell 2013. Accordingly, a vertical steering angle θvof the third beam steering cell 2013 may have a positive value.

On the other hand, the plurality of nanopillars 10 may form ananopattern in which an attribute decreases in a direction from thecenter of the first beam steering unit 201 toward each of the beamsteering cells 2011, 2012, and 2013.

Referring to FIG. 22, the plurality of nanopillars 10 included in thesecond beam steering cell 2012 located at the center of the first beamsteering unit 201 may form a nanopattern in which an attribute relatedto at least one of the width W, height H, and number per unit length isuniform. Accordingly, a steering angle of the second beam steering cell2012 may be 0°.

In this case, the plurality of nanopillars 10 included in the first beamsteering cell 2011 located at the left of the second beam steering cell2012 may form a nanopattern in which an attribute related to at leastone of the width W, height H, and number per unit length of thenanopillars 10 decreases in a direction from the center of the firstbeam steering unit 201 toward the first beam steering cell 2011.Accordingly, a vertical steering angle θv of the first beam steeringcell 2011 may have a positive value.

Likewise, the plurality of nanopillars 10 included in the third beamsteering cell 2013 located at the right of the second beam steering cell2012 may form a nanopattern in which an attribute related to at leastone of the width W, height H, and number per unit length of thenanopillars 10 decreases in a direction from the center of the firstbeam steering unit 201 toward the third beam steering cell 2013.Accordingly, a vertical steering angle θv of the third beam steeringcell 2013 may have a negative value.

The second beam steering unit 202 may obtain a laser beam steered by thefirst beam steering unit 201.

The second beam steering unit 202 may include a plurality of beamsteering cells 2021, 2022, and 2023.

The second beam steering unit 202 may steer the obtained laser beamusing a plurality of nanopillars 10.

As illustrated in FIG. 23, the second beam steering unit 202 maygenerate a laser beam having a shape diverging along the h-axis. Forexample, a horizontal steering angle θh of the second beam steering unit202 may be in the range of −60° to 60°.

In this case, the plurality of nanopillars 10 included in the secondbeam steering unit 202 may form a subwavelength pattern in which a widthW thereof increases along the h-axis.

Specifically, the plurality of nanopillars 10 included in the secondbeam steering unit 202 may form, in a direction away from the center ofthe second beam steering unit 202 along the h-axis, a nanopattern inwhich the width W thereof increases.

Likewise, the plurality of nanopillars 10 included in the second beamsteering unit 202 may form nanopatterns on the basis of locations of theplurality of beam steering cells 2021, 2022, and 2023.

Meanwhile, a vertical steering angle θv of FIG. 21 may be smaller than ahorizontal steering angle θ of FIG. 23. Accordingly, a horizontal rangeof the FOV of the laser emitting device 1000 may be wider than avertical range of the FOV.

Meanwhile, the steering performance of the second beam steering unit 202may vary according to an angle of incidence of a laser beam incident onthe second beam steering unit 202. Specifically, the steeringperformance of the second beam steering unit 202 may be improved asangle of incidence of the laser beam is closer to 90°. Here, angle ofincidence may refer to an angle between the second support unit 302 andthe incident laser beam.

In other words, the steering performance of the second beam steeringunit 202 may be related to a steering angle of the first beam steeringunit 201. Specifically, the steering performance of the second beamsteering unit 202 may be improved as the steering angle of the firstbeam steering unit 201 becomes smaller.

Accordingly, the first steering angle of the first beam steering unit201 may be smaller than the second steering angle of the second beamsteering unit 202. That is, the first beam steering unit 201 may steer alaser beam in the vertical direction in which the steering angle isrelatively small, and the second beam steering unit 202 may steer alaser beam in the horizontal direction in which the steering angle isrelatively large.

Accordingly, the steering performance of the laser emitting device 1000may be improved.

Meanwhile, although a nanopattern due to a change in the width W of thenanopillars 10 has been described as an example with reference to FIGS.21 to 23, the plurality of nanopillars 10 included in the beam steeringunit 200 may form a nanopattern on the basis of changes in the height Hand number per unit length. This should be sufficiently understood fromthe principle described above with reference to FIGS. 2 to 7.

Meanwhile, steering directions of the first beam steering unit 201 andthe second beam steering unit 202 may be switched with each other. Thatis, the first beam steering unit 201 may steer a laser beam in theh-direction, and the second beam steering unit 202 may steer a laserbeam in the v-direction.

FIG. 24 is an exploded perspective view of a laser emitting deviceaccording to another embodiment.

Referring to FIG. 24, a laser emitting device 1000 may include a laseremitting unit 100 and a beam steering unit 200. The beam steering unit200 may include a first beam steering unit 201 and a second beamsteering unit 202.

An operation principle of the laser emitting device 1000 may be the sameas that of the laser emitting device 1000 of FIG. 20 except for steeringdirections of the first and second beam steering units 201 and 202.Accordingly, differences from the laser emitting device 1000 of FIG. 20will be mainly described below.

The first beam steering unit 201 may generate a laser beam having ashape diverging in the h-direction. A horizontal steering angle θh ofthe first beam steering unit 201 may be in the range of −60° to 60°.

In this case, a plurality of nanopillars 10 included in the first beamsteering unit 201 may form a subwavelength pattern in which at least oneattribute of the width W, height H, and number per unit lengthrepeatedly increases in the h-direction.

The second beam steering unit 202 may be disposed at an upper portion ofthe first beam steering unit 201 to obtain a laser beam steered by thefirst beam steering unit 201. The second beam steering unit 202 maygenerate laser beams of various shapes by steering the laser beamobtained from the first beam steering unit 201.

Specifically, the second beam steering unit 202 may steer the obtainedlaser beam using the plurality of nanopillars 10. The second beamsteering unit 202 may include a metasurface.

The second beam steering unit 202 may steer a laser beam in theh-direction corresponding to the horizontal direction and thev-direction corresponding to the vertical direction.

For example, the second beam steering unit 202 may generate a laser beamhaving a shape diverging in the v-direction. A vertical steering angleθv of the second beam steering unit 202 may be in the range of −15° to15°.

In this case, the plurality of nanopillars 10 included in the secondbeam steering unit 202 may form a subwavelength pattern in which atleast one attribute of the width W, height H, and number per unit lengthrepeatedly increases in the h-direction.

Meanwhile, although some of the laser beams steered by the first beamsteering unit 201 are seen in FIG. 24 as being projected to the outsideof the second beam steering unit 202, this is merely for convenience ofdescription, and some of the laser beams are not projected to theoutside of the second beam steering unit 202 in reality.

FIG. 25 is an exploded perspective view of a laser emitting deviceaccording to still another embodiment.

Referring to FIG. 25, a laser emitting device 1000 may include a laseremitting unit 100 and a beam steering unit 200. The beam steering unit200 may include a first beam steering unit 201 and a second beamsteering unit 202.

An operation principle of the laser emitting device 1000 may be the sameas that of the laser emitting device 1000 of FIG. 20, except forsteering directions and angles of the first and second beam steeringunits 201 and 202. Accordingly, differences from the laser emittingdevice 1000 of FIG. 20 will be mainly described below.

The first beam steering unit 201 may generate a laser beam having ashape diverging in the h-direction and v-direction. In this case, ahorizontal steering angle θh of the first beam steering unit 201 may bein the range of −20° to 20°. Also, a vertical steering angle θv of thefirst beam steering unit 201 may be in the range of −5° to 5°.

In this case, a plurality of nanopillars 10 included in the first beamsteering unit 201 may form a subwavelength pattern in which at least oneattribute of the width W, height H, and number per unit lengthrepeatedly increases in the h-direction.

Also, the plurality of nanopillars 10 included in the first beamsteering unit 201 may form a subwavelength pattern in which at least oneattribute of the width W, height H, and number per unit lengthrepeatedly increases in the v-direction.

The second beam steering unit 202 may be disposed at an upper portion ofthe first beam steering unit 201 to obtain a laser beam steered by thefirst beam steering unit 201. The second beam steering unit 202 maygenerate laser beams of various shapes by steering the laser beamobtained from the first beam steering unit 201.

Specifically, the second beam steering unit 202 may steer the obtainedlaser beam using the plurality of nanopillars 10. The second beamsteering unit 202 may include a metasurface.

The second beam steering unit 202 may steer a laser beam in theh-direction corresponding to the horizontal direction and thev-direction corresponding to the vertical direction.

The second beam steering unit 202 may generate a laser beam having ashape diverging in the v-direction and the h-direction.

For example, the second beam steering unit 202 may steer a laser beamsteered by the first beam steering unit 201 in the range of −10° to 10°in the h-direction. Accordingly, the laser beam steered by the secondbeam steering unit 202 may be emitted at a steering angle in the rangeof −15° to 15°, which is the sum of the steering angle by the first beamsteering unit 201 and the steering angle by the second beam steeringunit 202.

Also, the second beam steering unit 202 may steer a laser beam steeredby the first beam steering unit 201 in the range of −40° to 40° in thev-direction. Accordingly, the laser beam steered by the second beamsteering unit 202 may be emitted at a steering angle in the range of−60° to 60°, which is the sum of the steering angle by the first beamsteering unit 201 and the steering angle by the second beam steeringunit 202.

The plurality of nanopillars 10 included in the second beam steeringunit 202 may form a subwavelength pattern in which at least oneattribute of the width W, height H, and number per unit lengthrepeatedly increases in the h-direction.

Also, the plurality of nanopillars 10 included in the second beamsteering unit 202 may form a subwavelength pattern in which at least oneattribute of the width W, height H, and number per unit lengthrepeatedly increases in the v-direction.

Meanwhile, although some of the laser beams steered by the first beamsteering unit 201 are seen in FIG. 25 as being projected to the outsideof the second beam steering unit 202, this is merely for convenience ofdescription, and some of the laser beams are not projected to theoutside of the second beam steering unit 202 in reality.

Sizes of the first beam steering unit 201 and the second beam steeringunit 202 may be different. For example, a cross-sectional area along theh-axis of the second beam steering unit 202 may be larger than across-sectional area along the h-axis of the first beam steering unit201.

FIG. 26 is an exploded perspective view of a laser emitting deviceaccording to yet another embodiment.

Referring to FIG. 26, a laser emitting device 1000 may include a laseremitting unit 100 and a beam steering unit 200. The beam steering unit200 may include a first beam steering unit 201 and a second beamsteering unit 202.

An operation principle of the laser emitting device 1000 may be the sameas that of the laser emitting device 1000 of FIG. 25, except for a sizerelationship between the first and second beam steering units 201 and202. Accordingly, differences from the laser emitting device 1000 ofFIG. 25 will be mainly described below.

FIGS. 27 and 28 are exploded perspective views of the laser emittingdevice of FIG. 26 viewed from the side. Specifically, FIG. 27 is anexploded perspective view of the laser emitting device of FIG. 26 viewedalong the h-axis. FIG. 28 is an exploded perspective view of the laseremitting device of FIG. 26 viewed along the v-axis.

Referring to FIG. 27, a length along the v-axis of the first beamsteering unit 201 may be smaller than a length along the v-axis of thesecond beam steering unit 202.

Accordingly, the second beam steering unit 202 may easily obtain a laserbeam steered by the first beam steering unit 201.

Specifically, when the first beam steering unit 201 generates a laserbeam diverging along the v-axis, some of the diverged laser beams may beemitted to the outside of the second beam steering unit 202.Accordingly, light loss may occur due to beam steering by the first beamsteering unit 201.

When the length along the v-axis of the second beam steering unit 202 islarger than the length along the v-axis of the first beam steering unit201, the light loss may be prevented.

Likewise, as illustrated in FIG. 28, when viewed along the v-axis, alength along the h-axis of the first beam steering unit 201 may besmaller than a length along the h-axis of the second beam steering unit202.

When the first beam steering unit 201 generates a laser beam divergingalong the h-axis, some of the diverged laser beams may be emitted to theoutside of the second beam steering unit 202. Accordingly, light lossmay occur due to beam steering of the first beam steering unit 201.

When the length along the h-axis of the second beam steering unit 202 islarger than the length along the h-axis of the first beam steering unit201, the light loss may be prevented.

Meanwhile, the length of the second beam steering unit 202 may be set onthe basis of a steering direction of the first beam steering unit 201.

For example, when the first beam steering unit 201 steers a laser beamalong the v-axis, the length along the v-axis of the second beamsteering unit 202 viewed along the h-axis may be larger than the lengthalong the v-axis of the first beam steering unit 201 viewed along theh-axis.

In this case, the length along the h-axis of the second beam steeringunit 202 viewed along the v-axis may be equal to the length along theh-axis of the first beam steering unit 201 viewed along the v-axis.

As another example, when the first beam steering unit 201 steers a laserbeam along the h-axis, a length along the h-axis of the second beamsteering unit 202 viewed along the v-axis may be larger than a lengthalong the h-axis of the first beam steering unit 201 viewed along thev-axis.

In this case, a length along the v-axis of the second beam steering unit202 viewed along the h-axis may be equal to a length along the v-axis ofthe first beam steering unit 201 viewed along the h-axis.

As still another example, when the first beam steering unit 201 steers alaser beam along the h-axis and v-axis, lengths along the v-axis andh-axis of the second beam steering unit 202 viewed along the v-axis andh-axis may be larger than lengths along the v-axis and h-axis of thefirst beam steering unit 201 viewed along the v-axis and h-axis.

Meanwhile, a length of the second beam steering unit 202 may be set onthe basis of a size of a steering angle of the first beam steering unit201.

For example, a length of the second beam steering unit 202 when asteering angle of the first beam steering unit 201 is a first angle maybe smaller than a length of the second beam steering unit 202 when thesteering angle of the first beam steering unit 201 is a second anglewhich is larger than the first angle.

Meanwhile, in FIGS. 27 and 28, as the plurality of nanopillars 10included in the first beam steering unit 201, portions of thenanopillars 10 in which changes in the width W are shown areillustrated. However, this is merely for convenience of description, andwhen the laser emitting device 1000 of FIG. 26 is viewed from the sidein reality, the sizes of the plurality of nanopillars 10 may also lookthe same.

Meanwhile, the laser emitting device 1000 has been described above withreference to FIGS. 19 to 28 as including two beam steering units 201 and202. However, embodiments are not limited thereto, and the laseremitting device 1000 may also include three or more beam steering units200.

The operation principles of the laser emitting device 1000 according tovarious embodiments have been described above.

Hereinafter, implementations in which the laser emitting device 1000 isapplied will be described.

FIG. 29 is a block diagram for describing a light detection and ranging(LiDAR) device according to an embodiment. The lidar device may refer toa device for obtaining information on a distance to a surrounding objectby using a laser.

Referring to FIG. 29, a lidar device 10000 according to an embodimentmay include a laser emitting device 1000, a sensor unit 2000, and acontrol unit 3000.

A laser beam emitted from the laser emitting device 1000 may beirradiated to an object and then sensed by the sensor unit 2000. Thecontrol unit 3000 may obtain information on a distance from the objecton the basis of a reception time point of the laser beam sensed by thesensor unit 2000 and an emission time point of the laser beam emittedfrom the laser emitting device 1000.

Each configuration of the lidar device 10000 will be described in detailbelow.

The laser emitting device 1000 may include a laser emitting unit 100 anda beam steering unit 200. Meanwhile, since the laser emitting device1000 may operate identically or similarly to the laser emitting devicedescribed above with reference to FIGS. 1 to 28, detailed descriptionthereof will be omitted.

The sensor unit 2000 may sense a laser beam reflected from an object.

The sensor unit 2000 may include a single sensor element or may alsoinclude a sensor array formed of a plurality of sensor elements. Forexample, the second unit 2000 may include an avalanche photodiode (APD)or may also include silicon photomultipliers (SiPM) formed of aplurality of single-photon avalanche diodes (SPADs).

The sensor unit 2000 may be provided as a single channel including aplurality of APDs. The sensor unit 2000 may also include a plurality ofchannels.

The sensor unit 2000 may include a charge-coupled device (CCD) and acomplementary metal-oxide-semiconductor (CMOS) image sensor.

The control unit 3000 may control the laser emitting unit 100 and thesensor unit 2000. For example, the control unit 3000 may control anemission time point, an emission cycle, and an intensity of a laser beamemitted from the laser emitting unit 100.

The control unit 3000 may obtain an emission time point of a laser beamemitted from the laser emitting unit 100. The control unit 3000 mayobtain a reception time point of a laser beam reflected from an objectand sensed by a sensor 1100. The control unit 3000 may obtain theinformation on a distance from the object using the emission time pointand the reception time point.

FIG. 30 is a block diagram for describing a lidar device according toanother embodiment.

Referring to FIG. 30, a lidar device 10000 according to an embodimentmay include a laser emitting unit 100, a beam steering unit 200, asensor unit 2000, and a control unit 3000.

Meanwhile, except for the beam steering unit 200, the lidar device ofFIG. 30 may operate identically to the lidar device of FIG. 29.Accordingly, detailed description on other configurations will beomitted, and the beam steering unit 200 will be mainly described.

The beam steering unit 200 may steer a laser beam emitted from the laseremitting unit 100 using a plurality of nanopillars.

The beam steering unit 200 may include a plurality of beam steeringmodules. For example, the beam steering unit 200 may include a firstbeam steering module 200 a and a second beam steering module 200 b.

Each of the first beam steering module 200 a and the second beamsteering module 200 b may include a plurality of nanopillars.

The plurality of nanopillars may form a subwavelength pattern on thebasis of at least one attribute of a width W, a pitch P, and a height H.

First nanopillars included in the first beam steering module 200 a mayform a subwavelength pattern on the basis of a first attribute.

Second nanopillars included in the second beam steering module 200 b mayform a subwavelength pattern on the basis of a second attribute.

The first attribute and the second attribute may be the same.

Meanwhile, the first beam steering module 200 a and the second beamsteering module 200 b may be disposed on different planes. For example,the second beam steering module 200 b may be disposed above the firstbeam steering module 200 a.

FIG. 31 is a block diagram for describing a lidar device according tostill another embodiment.

Referring to FIG. 31, a lidar device 10000 according to an embodimentmay include a laser emitting unit 100, a beam steering unit 200, asensor unit 2000, a control unit 3000, and a scanning unit 4000.

Meanwhile, except for including the scanning unit 4000, the lidar deviceof FIG. 31 may operate identically to the lidar device of FIG. 29.Accordingly, detailed description on other configurations will beomitted, and the scanning unit 4000 will be mainly described.

A laser beam emitted from the laser emitting unit 100 may be steered bythe beam steering unit 200. The beam steering unit 200 may irradiate thelaser beam emitted from the laser emitting unit 100 toward an objectthrough the scanning unit 4000. The sensor unit 2000 may receive thelaser beam reflected from the object through the scanning unit 4000. Thecontrol unit 3000 may obtain a distance from the lidar device 10000 tothe object using an emission time point of the emitted laser beam and areception time point of the received laser beam.

The scanning unit 4000 according to an embodiment may obtain the laserbeam emitted from the laser emitting device 1000. The scanning unit 4000may reflect the obtained laser beam toward an object.

The scanning unit 4000 may obtain a laser beam reflected from theobject. The scanning unit 4000 may reflect the obtained laser beamtoward the sensor unit.

The scanning unit 4000 may steer a laser beam emitted from the laseremitting device 1000. For example, the scanning unit 4000 may change aflight path of the emitted laser beam by reflecting the emitted laserbeam. Alternatively, the scanning unit 4000 may change the flight pathof the emitted laser beam by refracting the emitted laser beam.

The scanning unit 4000 may form laser beams in various patterns. Forexample, the scanning unit 4000 may form a laser beam of a line patternfrom a laser beam in the form of a point light source. Alternatively,the scanning unit 4000 may form a laser beam in a planar pattern from alaser beam of a line pattern.

The scanning unit 4000 may form the FOV including a plurality ofscanning points distributed in the vertical direction and horizontaldirection.

The scanning unit 4000 may include various optical configurations.

For example, the scanning unit 4000 may include a scanning mirrorconfigured to reflect light. Specifically, the scanning mirror mayinclude a plane mirror, a micro-electro-mechanical-system (MEMS) mirror,a galvano mirror, and a polygonal mirror.

Also, the scanning unit 4000 may include a lens and a collimator.

FIG. 32 is a pictorial diagram illustrating a lidar device according toan implementation.

Referring to FIG. 32, a lidar device 10000 may include a laser emittingdevice 1000, a sensor unit 2000, and a polygonal mirror 4100.

A laser beam emitted from the laser emitting device 1000 may beprojected toward an object through the polygonal mirror 4100. A laserbeam reflected from the object may be received by the sensor unit 2000through the polygonal mirror 4100.

Each configuration of the lidar device will be described in detailbelow.

The laser emitting device 1000 may emit a laser beam toward thepolygonal mirror 4100. Specifically, the laser emitting device 1000 mayemit a laser beam to an upper portion of a reflective surface of thepolygonal mirror 4100.

The laser emitting device 1000 may emit laser beams of various forms.For example, the laser emitting device 1000 may emit a beam of a linepattern extending along a rotation axis of the polygonal mirror 4100.

The laser beam emitted from the laser emitting device 1000 may beprojected to a reflective surface of the polygonal mirror 4100.

The polygonal mirror 4100 may change a flight path of the laser beamemitted from the laser emitting device 1000. For example, the polygonalmirror 4100 may change the flight path of the laser beam by reflectingthe emitted laser beam.

The polygonal mirror 4100 may project the emitted laser beam toward anobject by reflecting the emitted laser beam.

The polygonal mirror 4100 may rotate about one axis. The polygonalmirror 4100 may form laser beams in various patterns by rotating 360°.For example, the polygonal mirror 4100 may form a laser beam in a planarpattern from a laser beam of a line pattern by rotating. Alternatively,the polygonal mirror 4100 may form a laser beam in a linear formextending along an axis perpendicular to the one axis from a laser beamin the form of a point light source.

The polygonal mirror 4100 may obtain a laser beam reflected from theobject. The polygonal mirror 4100 may reflect the obtained laser beamtoward the sensor unit 2000.

The polygonal mirror 4100 may obtain laser beams reflected from theobject through the reflective surface.

The polygonal mirror 4100 may reflect a laser beam obtained through alower portion of the reflective surface among the obtained laser beamsto the sensor unit 2000.

The polygonal mirror 4100 may have various shapes. For example, thepolygonal mirror 4100 may have a polygonal column shape.

The polygonal mirror 4100 may include a plurality of reflectivesurfaces. For example, the polygonal mirror 4100 may include fourreflective surfaces.

The sensor unit 2000 may receive a laser beam reflected from thepolygonal mirror 4100. Specifically, the sensor unit 2000 may receive alaser beam reflected from an object through the polygonal mirror 4100.

The sensor unit 2000 may be located at the same side as the laseremitting device 1000 with respect to the polygonal mirror 4100. Forexample, the sensor unit 2000 may be disposed at a lower portion of thelaser emitting device 1000.

Meanwhile, the laser emitting device 1000 may include a laser emittingunit including a plurality of VCSEL elements and a beam steering unitincluding a plurality of nanopillars.

FIG. 33 is a view for describing a lidar device according to animplementation. Specifically, FIG. 33 is an exploded perspective view ofthe laser emitting device 1000 of FIG. 32.

Referring to FIG. 33, a lidar device 10000 may include a laser emittingdevice 1000, a sensor unit 2000, and a polygonal mirror 4100.

The laser emitting device 1000 may include a laser emitting unit 100 anda beam steering unit 200.

Each configuration of the laser emitting device 1000 may be described indetail below.

The laser emitting unit 100 according to an embodiment may include aplurality of VCSEL elements.

The plurality of VCSEL elements may be arranged in the form of an arrayalong a rotation axis of the polygonal mirror 4100.

The plurality of VCSEL elements may emit a laser beam in a directionperpendicular to an emission surface of the laser emitting unit 100.

The laser emitting unit 100 may emit a laser beam toward the beamsteering unit 200.

The laser emitting unit 100 may emit a laser beam in a directionperpendicular to the rotation axis of the polygonal mirror 4100.

The beam steering unit 200 according to an embodiment may steer a laserbeam emitted from the laser emitting unit 100 along the rotation axis.

The beam steering unit 200 may generate a laser beam of a line patternextending along the rotation axis from the laser beam emitted from thelaser emitting unit 100.

The beam steering unit 200 may include a plurality of beam steeringcells 210 each including a plurality of nanopillars 10.

For example, the beam steering cells 210 may include a first beamsteering cell 211, a second beam steering cell 212, a third beamsteering cell 213, a fourth beam steering cell 214, and a fifth beamsteering cell 215.

Each of the first to fifth beam steering cells 211, 212, 213, 214, and215 may steer a laser beam using the plurality of nanopillars 10. Forexample, each of the first to fifth beam steering cells 211, 212, 213,214, and 215 may steer a laser beam emitted from the laser emitting unit100 along the rotation axis of the polygonal mirror 4100 by using theplurality of nanopillars 10.

The first to fifth beam steering cells 211, 212, 213, 214, and 215 maybe arranged in the form of an array along the rotation axis.

The plurality of nanopillars 10 may steer a laser beam emitted from thelaser emitting unit 100.

The plurality of nanopillars 10 may form a subwavelength pattern on thebasis of at least one attribute of the width W, height H, and number perunit length thereof. For example, the plurality of nanopillars 10 mayform a subwavelength pattern on the basis of locations at which theplurality of beam steering cells 211, 212, 213, 214, and 215 arearranged in the array in which the plurality of beam steering cells 211,212, 213, 214, and 215 are arranged.

Specifically, the plurality of nanopillars 10 may form, in a directionfrom the center of the array toward the beam steering cell 210 in whichthe plurality of nanopillars 10 are included, a subwavelength pattern inwhich an attribute repeatedly increases.

Accordingly, the plurality of nanopillars 10 which are included in thefirst beam steering cell 211 located at the top of the array may form asubwavelength pattern in which an attribute gradually increases towardthe top of the array.

On the other hand, the plurality of nanopillars 10 which are included inthe fifth beam steering cell 215 located at the bottom of the array mayform a subwavelength pattern in which an attribute gradually increasestoward the bottom of the array.

Also, the plurality of nanopillars 10 which are included in the thirdbeam steering cell 213 located at the center of the array may form asubwavelength pattern in which an attribute is uniform.

Meanwhile, the plurality of nanopillars 10 may form a subwavelengthpattern in which a change rate of an attribute becomes gradually higherthe farther the beam steering cell 210 is from the center of the array.For example, a change rate of a first attribute of the plurality ofnanopillars 10 included in the first beam steering cell 211 may behigher than a change rate of a second attribute of the plurality ofnanopillars 10 included in the second beam steering cell 212.

Accordingly, a size of a rotation-axis component of a steering angle ofthe beam steering cell 210 may gradually increase away from the centerof the array. For example, a size of a rotation-axis component of afirst steering angle of the first beam steering cell 211 may be largerthan a size of a rotation-axis component of a second steering angle ofthe second beam steering cell 212.

In this way, the size along the rotation axis of a laser beam emittedfrom the laser emitting device 1000 may gradually increase from thelaser emitting device 1000 toward the polygonal mirror 4100.

Accordingly, a second length L2 along the rotation axis of the polygonalmirror 4100 may be larger than a first length L1 along the rotation axisof the array in which the plurality of beam steering cells 211, 212,213, 214, and 215 are arranged.

That is, a length along the rotation axis of a laser beam reflected fromthe polygonal mirror 4100 and projected to an object may be larger thana length along the rotation axis of a laser beam emitted from the laseremitting unit 100.

Accordingly, among measurable ranges of the lidar device 10000, a rangealong the rotation axis may be increased. Accordingly, short-rangeobject measurement performance of the lidar device 10000 may beimproved.

Also, as the length along the rotation axis of the polygonal mirror4100, that is, a height of the polygonal mirror 4100, increases, areception amount of the laser beam reflected from an object mayincrease. Accordingly, a measurable distance of the lidar device 10000may increase.

Meanwhile, a direction of a rotation-axis component of a steeringdirection of a beam steering cell 210 located at the top of the array inwhich the beam steering cells 210 are arranged may be opposite to adirection of a rotation-axis component of a steering direction of a beamsteering cell 210 located at the bottom of the array.

For example, a direction of a rotation-axis component of a firststeering direction of the first beam steering cell 211 may be oppositeto a direction of a rotation-axis component of a fifth steeringdirection of the fifth beam steering cell 215.

The sensor unit 2000 may receive a laser beam reflected from thepolygonal mirror 4100. Specifically, the sensor unit 2000 may receive alaser beam reflected from an object through the polygonal mirror 4100.

The sensor unit 2000 may be located at the same side as the laseremitting device 1000 with respect to the polygonal mirror 4100. Forexample, the sensor unit 2000 may be disposed at a lower portion of thelaser emitting device 1000.

Meanwhile, although, for convenience of description, the plurality ofbeam steering cells 211, 212, 213, 214, and 215 have been illustrated inFIG. 33 as being arranged in one-dimension, embodiments are not limitedthereto, and the plurality of beam steering cells 211, 212, 213, 214,and 215 may also be arranged in the form of a two-dimensional array. Forexample, the first to fourth beam steering cells 211, 212, 213, and 214may be arranged in the form of a 2×2 array.

FIG. 34 is a view for describing a lidar device according to anotherimplementation.

Referring to FIG. 34, a lidar device 10000 may include a laser emittingdevice 1000, a sensor unit 2000, and a polygonal mirror 4100.

The laser emitting device 1000 may include a laser emitting unit 100 anda beam steering unit 200.

Meanwhile, the laser emitting unit of FIG. 34 may correspond to thelaser emitting unit of FIG. 33. Accordingly, detailed descriptionthereof will be omitted, and differences from the lidar device of FIG.33 will be mainly described below.

The beam steering unit 200 according to an embodiment may steer a laserbeam emitted from the laser emitting unit 100 along the rotation axis.

The beam steering unit 200 may generate a laser beam of a line patternextending along the rotation axis from the laser beam emitted from thelaser emitting unit 100.

The beam steering unit 200 may include a plurality of beam steeringcells 210 each including a plurality of nanopillars 10.

For example, the beam steering cells 210 may include a first beamsteering cell 211, a second beam steering cell 212, a third beamsteering cell 213, a fourth beam steering cell 214, and a fifth beamsteering cell 215.

Each of the first to fifth beam steering cells 211, 212, 213, 214, and215 may steer a laser beam using the plurality of nanopillars 10. Forexample, each of the first to fifth beam steering cells 211, 212, 213,214, and 215 may steer a laser beam emitted from the laser emitting unit100 along a rotation axis of a polygonal mirror 4100 by using theplurality of nanopillars 10.

The first to fifth beam steering cells 211, 212, 213, 214, and 215 maybe arranged in the form of an array along the rotation axis.

The plurality of nanopillars 10 may steer a laser beam emitted from thelaser emitting unit 100.

The plurality of nanopillars 10 may form a subwavelength pattern on thebasis of at least one attribute of the width W, height H, and number perunit length thereof. For example, the plurality of nanopillars 10 mayform a subwavelength pattern on the basis of locations at which theplurality of beam steering cells 211, 212, 213, 214, and 215 arearranged in the array in which the plurality of beam steering cells 211,212, 213, 214, and 215 are arranged.

Specifically, the plurality of nanopillars 10 may form, in a directionfrom the center of the array toward the beam steering cell 210 in whichthe plurality of nanopillars 10 are included, a subwavelength pattern inwhich an attribute repeatedly decreases.

Accordingly, the plurality of nanopillars 10 which are included in thefirst beam steering cell 211 located at the top of the array may form asubwavelength pattern in which an attribute gradually decreases towardthe top of the array.

On the other hand, the plurality of nanopillars 10 which are included inthe fifth beam steering cell 215 located at the bottom of the array mayform a subwavelength pattern in which an attribute gradually decreasestoward the bottom of the array.

Also, the plurality of nanopillars 10 which are included in the thirdbeam steering cell 213 located at the center of the array may form asubwavelength pattern in which an attribute is uniform.

Meanwhile, the plurality of nanopillars 10 may form a subwavelengthpattern in which a change rate of attribute becomes gradually higher thefarther the beam steering cell 210 is from the center of the array. Forexample, a change rate of a first attribute of the plurality ofnanopillars 10 included in the first beam steering cell 211 may behigher than a change rate of a second attribute of the plurality ofnanopillars 10 included in the second beam steering cell 212.

Accordingly, a size of a rotation-axis component of a steering angle ofthe beam steering cell 210 may gradually increase away from the centerof the array. For example, a size of a rotation-axis component of afirst steering angle of the first beam steering cell 211 may be largerthan a size of a rotation-axis component of a second steering angle ofthe second beam steering cell 212.

In this way, the size along the rotation axis of a laser beam emittedfrom the laser emitting device 1000 may gradually decrease from thelaser emitting device 1000 toward the polygonal mirror 4100.

Accordingly, a second length L2 along the rotation axis of the polygonalmirror 4100 may be smaller than a first length L1 along the rotationaxis of the array in which the plurality of beam steering cells 211,212, 213, 214, and 215 are arranged.

Accordingly, the polygonal mirror 4100 may be manufactured in a smallersize. That is, as the size of the polygonal mirror 4100 is reduced, thelidar device 10000 may be manufactured in a smaller size.

Also, as the size of the polygonal mirror 4100 is reduced, a load of amotor which provides a rotary force to the polygonal mirror 4100 may bereduced.

The sensor unit 2000 may receive a laser beam reflected from thepolygonal mirror 4100. Specifically, the sensor unit 2000 may receive alaser beam reflected from an object through the polygonal mirror 4100.

Meanwhile, the sensor unit 2000 may be disposed at an opposite side fromthe laser emitting device 1000 with respect to the polygonal mirror4100.

The sensor unit 2000 may receive a laser beam reflected from an objectthrough a second reflective surface of the polygonal mirror 4100, whichis different from a first reflective surface thereof to which a laserbeam emitted from the laser emitting device 1000 is projected.

Accordingly, interference between a first laser beam projected to anobject through the first reflective surface and a second laser beamreflected from the object to the second reflective surface may beprevented.

FIG. 35 is a view for describing a lidar device according to stillanother implementation.

Referring to FIG. 35, a lidar device 10000 may include a laser emittingdevice 1000, a sensor unit 2000, and a nodding mirror 4200.

The laser emitting device 1000 may include a laser emitting unit 100 anda beam steering unit 200.

Meanwhile, the laser emitting unit of FIG. 35 may correspond to thelaser emitting unit of FIG. 33. Accordingly, detailed descriptionthereof will be omitted, and differences from the lidar device of FIG.33 will be mainly described below.

The beam steering unit 200 according to an embodiment may steer a laserbeam emitted from the laser emitting unit 100 along the rotation axis.

The beam steering unit 200 may generate a laser beam of a line patternextending along the rotation axis from the laser beam emitted from thelaser emitting unit 100.

The beam steering unit 200 may include a plurality of beam steeringcells 210 each including a plurality of nanopillars 10.

For example, the beam steering cells 210 may include a first beamsteering cell 211, a second beam steering cell 212, a third beamsteering cell 213, a fourth beam steering cell 214, and a fifth beamsteering cell 215.

Each of the first to fifth beam steering cells 211, 212, 213, 214, and215 may steer a laser beam using the plurality of nanopillars 10. Forexample, each of the first to fifth beam steering cells 211, 212, 213,214, and 215 may steer a laser beam emitted from the laser emitting unit100 along a rotation axis of the nodding mirror 4200 by using theplurality of nanopillars 10.

The first to fifth beam steering cells 211, 212, 213, 214, and 215 maybe arranged in the form of an array along the rotation axis.

The plurality of nanopillars 10 may steer a laser beam emitted from thelaser emitting unit 100.

The plurality of nanopillars 10 may form a subwavelength pattern on thebasis of at least one attribute of the width W, height H, and number perunit length thereof. For example, the plurality of nanopillars 10 mayform a subwavelength pattern on the basis of locations at which theplurality of beam steering cells 211, 212, 213, 214, and 215 arearranged in the array in which the plurality of beam steering cells 211,212, 213, 214, and 215 are arranged.

Specifically, the plurality of nanopillars 10 may form, in a directionfrom the center of the array toward the beam steering cell 210 in whichthe plurality of nanopillars 10 are included, a subwavelength pattern inwhich an attribute repeatedly decreases.

Accordingly, the plurality of nanopillars 10 which are included in thefirst beam steering cell 211 located at the top of the array may form asubwavelength pattern in which an attribute gradually decreases towardthe top of the array.

On the other hand, the plurality of nanopillars 10 which are included inthe fifth beam steering cell 215 located at the bottom of the array mayform a subwavelength pattern in which an attribute gradually decreasestoward the bottom of the array.

Also, the plurality of nanopillars 10 which are included in the thirdbeam steering cell 213 located at the center of the array may form asubwavelength pattern in which an attribute is uniform.

Meanwhile, the plurality of nanopillars 10 may form a subwavelengthpattern in which a change rate of attribute becomes gradually higher thefarther the beam steering cell 210 is from the center of the array. Forexample, a change rate of a first attribute of the plurality ofnanopillars 10 included in the first beam steering cell 211 may behigher than a change rate of a second attribute of the plurality ofnanopillars 10 included in the second beam steering cell 212.

Accordingly, a size of a rotation-axis component of a steering angle ofthe beam steering cell 210 may gradually increase away from the centerof the array. For example, a size of a rotation-axis component of afirst steering angle of the first beam steering cell 211 may be largerthan a size of a rotation-axis component of a second steering angle ofthe second beam steering cell 212.

In this way, the size along the rotation axis of a laser beam emittedfrom the laser emitting device 1000 may gradually decrease from thelaser emitting device 1000 toward the nodding mirror 4200.

Accordingly, a third length L3 along the rotation axis of the noddingmirror 4200 may be smaller than a first length L1 along the rotationaxis of the array in which the plurality of beam steering cells 211,212, 213, 214, and 215 are arranged.

Accordingly, the nodding mirror 4200 may be manufactured in a smallersize. That is, as the size of the nodding mirror 4200 is reduced, thelidar device 10000 may be manufactured in a smaller size.

Meanwhile, the nodding mirror 4200 may be a MEMS mirror. In this case, arotational speed of the nodding mirror 4200 may be higher than arotational speed of the polygonal mirror 4100 of FIG. 33. Accordingly, ascanning speed of the lidar device 10000 may be increased.

Also, since, in comparison to the lidar device of FIG. 33, the lidardevice of FIG. 35 does not include a motor providing a rotary force,durability may be improved.

The sensor unit 2000 may receive a laser beam reflected from the noddingmirror 4200. Specifically, the sensor unit 2000 may receive a laser beamreflected from an object through the nodding mirror 4200.

Meanwhile, the lidar device 10000 may include a condensing lens 4300 forincreasing an amount of laser beam received from an object to thenodding mirror 4200.

The condensing lens 4300 may obtain a laser beam reflected from theobject. The obtained laser beam may be transmitted to the nodding mirror4200.

Meanwhile, the nodding mirror 4200 may rotate within a preset range. Forexample, a rotation range of the nodding mirror 4200 may be −15° to 15°.

Accordingly, the sensor unit 2000 configured to receive a laser beamreflected from an object through the nodding mirror 4200 may be locatedat the same side as the laser emitting device 1000 with respect to thenodding mirror 4200.

FIG. 36 is a top view of the lidar device of FIG. 35 viewed from thetop.

Referring to FIG. 36, a lidar device 10000 may include a laser emittingdevice 1000 and a nodding mirror 4200.

The nodding mirror 4200 may project a laser beam emitted from the laseremitting device 1000 toward an object by rotating within a predeterminedrange about a rotation axis.

Meanwhile, the laser emitting device 1000 may emit a laser beam towardthe rotation axis of the nodding mirror 4200. That is, a virtual linealong which the laser beam emitted from the laser emitting device 1000extends may cross the rotation axis of the nodding mirror 4200.

FIG. 37 is a view for describing a lidar device according to stillanother implementation.

Referring to FIG. 37, a lidar device 10000 may include a laser emittingdevice 1000, a sensor unit 2000, a nodding mirror 4200, and a condensinglens 4300.

The laser emitting device 1000 may include a laser emitting unit 100 anda beam steering unit 200.

Meanwhile, the laser emitting device 1000 and the nodding mirror 4200 ofFIG. 37 may operate identically to the laser emitting device 1000 andthe nodding mirror 4200 of FIG. 35. Accordingly, detailed descriptionthereof will be omitted, and differences with the lidar device of FIG.35 will be mainly described below.

The nodding mirror 4200 may guide a laser beam emitted from the laseremitting device 1000 to an object. For example, the nodding mirror 4200may guide the emitted laser beam to the object by reflecting the emittedlaser beam.

The nodding mirror 4200 may rotate about an axis in a direction in whichfirst to fifth beam steering cells 211, 212, 213, 214, and 215 arearranged. Alternatively, the nodding mirror 4200 may rotate about anaxis perpendicular to an emission direction of a laser beam emitted fromthe laser emitting unit 100.

The nodding mirror 4200 may form a laser beam in a planar form from alaser beam in a linear form by rotating about axis. That is, the noddingmirror 4200 may form a laser beam point cloud.

The nodding mirror 4200 may irradiate the laser beam in the planar formto an object.

The sensor unit 2000 may receive a laser beam reflected from the object.

The condensing lens 4300 may be disposed between the sensor unit 2000and the object to obtain the laser beam reflected from the object. Theobtained laser beam may be obtained by the sensor unit 2000.

The sensor unit 2000 may include a plurality of sensor elements arrangedin the form of an array. For example, the plurality of sensor elementsmay be arranged in a direction parallel to a direction in which thefirst to fifth beam steering cells 211, 212, 213, 214, and 215 arearranged.

According to an embodiment, the size of a lidar device can be reduced byusing a VCSEL element.

According to another embodiment, a scanning point cloud can be generatedby forming various subwavelength patterns using nanopillars.

According to still another embodiment, a solid-state lidar devicecapable of 3D scanning can be realized using a metasurface.

Advantageous effects of the present disclosure are not limited to thosedescribed above, and other unmentioned advantageous effects should beclearly understood by those of ordinary skill in art to which thepresent disclosure pertains from the present specification andaccompanying drawings.

The method according to an embodiment may be implemented in the form ofa program command that is executable by various computer means and maybe recorded in a computer readable recording medium. The computerreadable recording medium may include a program command, a data file, adata structure, and the like solely or in combination. The programcommand recorded in the medium may be particularly designed for theembodiment or may be known and usable by one of ordinary skill in thecomputer software art. Examples of the computer readable recordingmedium include hardware devices particularly configured to store andexecute program commands such as magnetic media such as a hard disk, afloppy disk, and a magnetic tape, optical media such as a compact diskread-only memory (CD-ROM) and a digital versatile disk (DVD),magneto-optical media such as a floptical disk, and semiconductorstorage devices such as a ROM, a random access memory (RAM), and a flashmemory. Examples of the program command include high-level languagecodes that are computer-executable by using an interpreter and the likeas well as machine language codes such as those formed by a compiler.Above-mentioned hardware device may be configured to serve as one ormore software modules to execute operations of the embodiment, and viceversa.

Although embodiments of the present disclosure have been described aboveusing limited embodiments and drawings, one of ordinary skill in artshould be capable of modifying and changing above-described embodimentsin various ways. For example, the above-described techniques may beperformed in a different order from the above-described method, and/orabove-described elements such as a system, a structure, a device, and acircuit may be coupled or combined in a different form fromabove-described method, or suitable results may be achieved even whenthe elements are replaced or substituted with other elements or theirequivalents.

Therefore, other implementations, embodiments, and equivalents ofappended claims also belong to the scope of the claims below.

What is claimed is:
 1. A lidar device comprising: a laser emittingmodule including a plurality of Vertical Cavity Surface Emitting Laser(VCSEL) elements emitting a laser beam and arranged along in a form ofan array; a metasurface including a plurality of nanopillars arranged onan emission surface side of the laser emitting module, and configured tosteer the emitted laser beam, wherein the metasurface includes aplurality of beam steering cells arranged in a form of an array andconfigured to steer the emitted laser beam; a polygonal mirror rotatingabout a rotational axis, reflecting the emitted laser beam toward anobject and receiving a reflected laser beam by the object; and a sensorunit receiving, via the polygonal mirror, the reflected laser beamreflected wherein the plurality of beam steering cells include a firstbeam steering cell and a second beam steering cell, wherein the secondbeam steering cell is located closer to a center of the metasurface thanthe first beam steering cell, wherein each of the plurality of beamsteering cells includes at least some of the plurality of nanopillars,wherein the nanopillars included in the first beam steering cell form afirst subwavelength pattern and the nanopillars included in the secondbeam steering cell form a second subwavelength pattern, wherein a firstchange rate of an attribute in the first beam steering cell is differentfrom a second change rate of the attribute in the second beam steeringcell, and wherein the attribute is related to at least one of a width, aheight, and a number per unit length.
 2. The lidar device of claim 1,wherein: a first steering direction of the first beam steering cell isdifferent from a second steering direction of the second beam steeringcell.
 3. The lidar device of claim 2, wherein a first point at which afirst laser beam steered by the first beam steering cell is irradiatedon the polygonal mirror is located above a second point at which asecond laser beam steered by the second beam steering cell is irradiatedon the polygonal mirror.
 4. The lidar device of claim 1, wherein a firstdistance between the first beam steering cell and the second beamsteering cell is greater than a second distance between a first pointand a second point, and wherein the first point is a point at which afirst laser beam steered by the first beam steering cell is irradiatedon the polygonal mirror and the second point is a point at which asecond laser beam steered by the second beam steering cell is irradiatedon the polygonal mirror.
 5. The lidar device of claim 1, wherein thefirst change rate of the attribute in the first beam steering cell isgreater than the second change rate of the attribute in the second beamsteering cell.
 6. The lidar device of claim 1, wherein a length of themetasurface along a direction of the rotational axis is smaller than alength of the polygonal mirror along the direction of the rotationalaxis.
 7. The lidar device of claim 1, wherein a length of themetasurface along a direction of the rotational axis is greater than alength of the polygonal mirror along the direction of the rotationalaxis.
 8. The lidar device of claim 1, wherein the laser emitting moduleemits the laser beam in a direction perpendicular to the rotation axisof the polygonal mirror.